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package jsr166e; |
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import jsr166e.LongAdder; |
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import java.util.Arrays; |
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import java.util.Map; |
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import java.util.Set; |
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import java.util.Collection; |
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import java.util.ConcurrentModificationException; |
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import java.util.NoSuchElementException; |
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import java.util.concurrent.ConcurrentMap; |
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import java.util.concurrent.ThreadLocalRandom; |
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import java.util.concurrent.locks.LockSupport; |
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import java.util.concurrent.locks.AbstractQueuedSynchronizer; |
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import java.io.Serializable; |
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/** |
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* are typically useful only when a map is not undergoing concurrent |
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* updates in other threads. Otherwise the results of these methods |
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* reflect transient states that may be adequate for monitoring |
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* purposes, but not for program control. |
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* or estimation purposes, but not for program control. |
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* |
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* <p> Resizing this or any other kind of hash table is a relatively |
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* slow operation, so, when possible, it is a good idea to provide |
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* estimates of expected table sizes in constructors. Also, for |
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* compatibility with previous versions of this class, constructors |
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* may optionally specify an expected {@code concurrencyLevel} as an |
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* additional hint for internal sizing. |
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* <p> The table is dynamically expanded when there are too many |
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* collisions (i.e., keys that have distinct hash codes but fall into |
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* the same slot modulo the table size), with the expected average |
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* effect of maintaining roughly two bins per mapping (corresponding |
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* to a 0.75 load factor threshold for resizing). There may be much |
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* variance around this average as mappings are added and removed, but |
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* overall, this maintains a commonly accepted time/space tradeoff for |
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* hash tables. However, resizing this or any other kind of hash |
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* table may be a relatively slow operation. When possible, it is a |
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* good idea to provide a size estimate as an optional {@code |
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* initialCapacity} constructor argument. An additional optional |
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* {@code loadFactor} constructor argument provides a further means of |
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* customizing initial table capacity by specifying the table density |
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* to be used in calculating the amount of space to allocate for the |
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* given number of elements. Also, for compatibility with previous |
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* versions of this class, constructors may optionally specify an |
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* expected {@code concurrencyLevel} as an additional hint for |
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* internal sizing. Note that using many keys with exactly the same |
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* {@code hashCode()} is a sure way to slow down performance of any |
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* hash table. |
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* |
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* <p>This class and its views and iterators implement all of the |
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* <em>optional</em> methods of the {@link Map} and {@link Iterator} |
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private static final long serialVersionUID = 7249069246763182397L; |
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|
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/** |
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* A function computing a mapping from the given key to a value, |
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* or {@code null} if there is no mapping. This is a place-holder |
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* for an upcoming JDK8 interface. |
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* A function computing a mapping from the given key to a value. |
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* This is a place-holder for an upcoming JDK8 interface. |
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*/ |
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public static interface MappingFunction<K, V> { |
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/** |
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* Returns a value for the given key, or null if there is no |
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* mapping. If this function throws an (unchecked) exception, |
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* the exception is rethrown to its caller, and no mapping is |
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* recorded. Because this function is invoked within |
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* atomicity control, the computation should be short and |
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* simple. The most common usage is to construct a new object |
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* serving as an initial mapped value. |
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* Returns a value for the given key, or null if there is no mapping |
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* |
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* @param key the (non-null) key |
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* @return a value, or null if none |
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* @return a value for the key, or null if none |
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*/ |
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V map(K key); |
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} |
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|
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/** |
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* A function computing a new mapping given a key and its current |
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* mapped value (or {@code null} if there is no current |
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* mapping). This is a place-holder for an upcoming JDK8 |
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* interface. |
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*/ |
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public static interface RemappingFunction<K, V> { |
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/** |
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* Returns a new value given a key and its current value. |
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* |
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* @param key the (non-null) key |
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* @param value the current value, or null if there is no mapping |
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* @return a value for the key, or null if none |
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*/ |
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V remap(K key, V value); |
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} |
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|
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/** |
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* A partitionable iterator. A Spliterator can be traversed |
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* directly, but can also be partitioned (before traversal) by |
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* creating another Spliterator that covers a non-overlapping |
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* portion of the elements, and so may be amenable to parallel |
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* execution. |
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* |
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* <p> This interface exports a subset of expected JDK8 |
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* functionality. |
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* |
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* <p>Sample usage: Here is one (of the several) ways to compute |
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* the sum of the values held in a map using the ForkJoin |
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* framework. As illustrated here, Spliterators are well suited to |
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* designs in which a task repeatedly splits off half its work |
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* into forked subtasks until small enough to process directly, |
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* and then joins these subtasks. Variants of this style can be |
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* also be used in completion-based designs. |
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* |
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* <pre> |
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* {@code ConcurrentHashMapV8<String, Long> m = ... |
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* // Uses parallel depth of log2 of size / (parallelism * slack of 8). |
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* int depth = 32 - Integer.numberOfLeadingZeros(m.size() / (aForkJoinPool.getParallelism() * 8)); |
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* long sum = aForkJoinPool.invoke(new SumValues(m.valueSpliterator(), depth, null)); |
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* // ... |
157 |
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* static class SumValues extends RecursiveTask<Long> { |
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* final Spliterator<Long> s; |
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* final int depth; // number of splits before processing |
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* final SumValues nextJoin; // records forked subtasks to join |
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* SumValues(Spliterator<Long> s, int depth, SumValues nextJoin) { |
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* this.s = s; this.depth = depth; this.nextJoin = nextJoin; |
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* } |
164 |
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* public Long compute() { |
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* long sum = 0; |
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* SumValues subtasks = null; // fork subtasks |
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* for (int d = depth - 1; d >= 0; --d) |
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* (subtasks = new SumValues(s.split(), d, subtasks)).fork(); |
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* while (s.hasNext()) // directly process remaining elements |
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* sum += s.next(); |
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* for (SumValues t = subtasks; t != null; t = t.nextJoin) |
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* sum += t.join(); // collect subtask results |
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* return sum; |
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* } |
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* } |
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* }</pre> |
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*/ |
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public static interface Spliterator<T> extends Iterator<T> { |
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/** |
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* Returns a Spliterator covering approximately half of the |
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* elements, guaranteed not to overlap with those subsequently |
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* returned by this Spliterator. After invoking this method, |
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* the current Spliterator will <em>not</em> produce any of |
184 |
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* the elements of the returned Spliterator, but the two |
185 |
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* Spliterators together will produce all of the elements that |
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* would have been produced by this Spliterator had this |
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* method not been called. The exact number of elements |
188 |
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* produced by the returned Spliterator is not guaranteed, and |
189 |
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* may be zero (i.e., with {@code hasNext()} reporting {@code |
190 |
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* false}) if this Spliterator cannot be further split. |
191 |
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* |
192 |
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* @return a Spliterator covering approximately half of the |
193 |
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* elements |
194 |
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* @throws IllegalStateException if this Spliterator has |
195 |
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* already commenced traversing elements. |
196 |
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*/ |
197 |
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Spliterator<T> split(); |
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|
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/** |
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* Returns a Spliterator producing the same elements as this |
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* Spliterator. This method may be used for example to create |
202 |
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* a second Spliterator before a traversal, in order to later |
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* perform a second traversal. |
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* |
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* @return a Spliterator covering the same range as this Spliterator. |
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* @throws IllegalStateException if this Spliterator has |
207 |
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* already commenced traversing elements. |
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*/ |
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Spliterator<T> clone(); |
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} |
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|
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/* |
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* Overview: |
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* |
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* The primary design goal of this hash table is to maintain |
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* concurrent readability (typically method get(), but also |
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* iterators and related methods) while minimizing update |
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* contention. |
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* contention. Secondary goals are to keep space consumption about |
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* the same or better than java.util.HashMap, and to support high |
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* initial insertion rates on an empty table by many threads. |
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* |
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* Each key-value mapping is held in a Node. Because Node fields |
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* can contain special values, they are defined using plain Object |
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* work off Object types. And similarly, so do the internal |
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* methods of auxiliary iterator and view classes. All public |
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* generic typed methods relay in/out of these internal methods, |
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* supplying null-checks and casts as needed. |
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* supplying null-checks and casts as needed. This also allows |
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* many of the public methods to be factored into a smaller number |
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* of internal methods (although sadly not so for the five |
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* variants of put-related operations). The validation-based |
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* approach explained below leads to a lot of code sprawl because |
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* retry-control precludes factoring into smaller methods. |
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* |
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* The table is lazily initialized to a power-of-two size upon the |
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* first insertion. Each bin in the table contains a list of |
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* Nodes (most often, zero or one Node). Table accesses require |
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* volatile/atomic reads, writes, and CASes. Because there is no |
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* other way to arrange this without adding further indirections, |
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* we use intrinsics (sun.misc.Unsafe) operations. The lists of |
241 |
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* nodes within bins are always accurately traversable under |
242 |
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* volatile reads, so long as lookups check hash code and |
243 |
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* non-nullness of value before checking key equality. (All valid |
244 |
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* hash codes are nonnegative. Negative values are reserved for |
245 |
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* special forwarding nodes; see below.) |
236 |
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* first insertion. Each bin in the table normally contains a |
237 |
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* list of Nodes (most often, the list has only zero or one Node). |
238 |
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* Table accesses require volatile/atomic reads, writes, and |
239 |
> |
* CASes. Because there is no other way to arrange this without |
240 |
> |
* adding further indirections, we use intrinsics |
241 |
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* (sun.misc.Unsafe) operations. The lists of nodes within bins |
242 |
> |
* are always accurately traversable under volatile reads, so long |
243 |
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* as lookups check hash code and non-nullness of value before |
244 |
> |
* checking key equality. |
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* |
246 |
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* We use the top two bits of Node hash fields for control |
247 |
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* purposes -- they are available anyway because of addressing |
248 |
> |
* constraints. As explained further below, these top bits are |
249 |
> |
* used as follows: |
250 |
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* 00 - Normal |
251 |
> |
* 01 - Locked |
252 |
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* 11 - Locked and may have a thread waiting for lock |
253 |
> |
* 10 - Node is a forwarding node |
254 |
> |
* |
255 |
> |
* The lower 30 bits of each Node's hash field contain a |
256 |
> |
* transformation of the key's hash code, except for forwarding |
257 |
> |
* nodes, for which the lower bits are zero (and so always have |
258 |
> |
* hash field == MOVED). |
259 |
|
* |
260 |
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* Insertion (via put or putIfAbsent) of the first node in an |
260 |
> |
* Insertion (via put or its variants) of the first node in an |
261 |
|
* empty bin is performed by just CASing it to the bin. This is |
262 |
< |
* on average by far the most common case for put operations. |
263 |
< |
* Other update operations (insert, delete, and replace) require |
264 |
< |
* locks. We do not want to waste the space required to associate |
265 |
< |
* a distinct lock object with each bin, so instead use the first |
266 |
< |
* node of a bin list itself as a lock, using plain "synchronized" |
267 |
< |
* locks. These save space and we can live with block-structured |
268 |
< |
* lock/unlock operations. Using the first node of a list as a |
269 |
< |
* lock does not by itself suffice though: When a node is locked, |
270 |
< |
* any update must first validate that it is still the first node, |
271 |
< |
* and retry if not. Because new nodes are always appended to |
272 |
< |
* lists, once a node is first in a bin, it remains first until |
273 |
< |
* deleted or the bin becomes invalidated. However, operations |
274 |
< |
* that only conditionally update can and sometimes do inspect |
275 |
< |
* nodes until the point of update. This is a converse of sorts to |
276 |
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* the lazy locking technique described by Herlihy & Shavit. |
262 |
> |
* by far the most common case for put operations under most |
263 |
> |
* key/hash distributions. Other update operations (insert, |
264 |
> |
* delete, and replace) require locks. We do not want to waste |
265 |
> |
* the space required to associate a distinct lock object with |
266 |
> |
* each bin, so instead use the first node of a bin list itself as |
267 |
> |
* a lock. Blocking support for these locks relies on the builtin |
268 |
> |
* "synchronized" monitors. However, we also need a tryLock |
269 |
> |
* construction, so we overlay these by using bits of the Node |
270 |
> |
* hash field for lock control (see above), and so normally use |
271 |
> |
* builtin monitors only for blocking and signalling using |
272 |
> |
* wait/notifyAll constructions. See Node.tryAwaitLock. |
273 |
> |
* |
274 |
> |
* Using the first node of a list as a lock does not by itself |
275 |
> |
* suffice though: When a node is locked, any update must first |
276 |
> |
* validate that it is still the first node after locking it, and |
277 |
> |
* retry if not. Because new nodes are always appended to lists, |
278 |
> |
* once a node is first in a bin, it remains first until deleted |
279 |
> |
* or the bin becomes invalidated (upon resizing). However, |
280 |
> |
* operations that only conditionally update may inspect nodes |
281 |
> |
* until the point of update. This is a converse of sorts to the |
282 |
> |
* lazy locking technique described by Herlihy & Shavit. |
283 |
|
* |
284 |
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* The main disadvantage of this approach is that most update |
284 |
> |
* The main disadvantage of per-bin locks is that other update |
285 |
|
* operations on other nodes in a bin list protected by the same |
286 |
|
* lock can stall, for example when user equals() or mapping |
287 |
< |
* functions take a long time. However, statistically, this is |
288 |
< |
* not a common enough problem to outweigh the time/space overhead |
289 |
< |
* of alternatives: Under random hash codes, the frequency of |
157 |
< |
* nodes in bins follows a Poisson distribution |
287 |
> |
* functions take a long time. However, statistically, under |
288 |
> |
* random hash codes, this is not a common problem. Ideally, the |
289 |
> |
* frequency of nodes in bins follows a Poisson distribution |
290 |
|
* (http://en.wikipedia.org/wiki/Poisson_distribution) with a |
291 |
< |
* parameter of 0.5 on average under the default loadFactor of |
292 |
< |
* 0.75. The expected number of locks covering different elements |
293 |
< |
* (i.e., bins with 2 or more nodes) is approximately 10% at |
294 |
< |
* steady state. Lock contention probability for two threads |
295 |
< |
* accessing distinct elements is roughly 1 / (8 * #elements). |
296 |
< |
* Function "spread" performs hashCode randomization that improves |
297 |
< |
* the likelihood that these assumptions hold unless users define |
298 |
< |
* exactly the same value for too many hashCodes. |
299 |
< |
* |
300 |
< |
* The table is resized when occupancy exceeds a threshold. Only |
301 |
< |
* a single thread performs the resize (using field "resizing", to |
302 |
< |
* arrange exclusion), but the table otherwise remains usable for |
303 |
< |
* reads and updates. Resizing proceeds by transferring bins, one |
304 |
< |
* by one, from the table to the next table. Upon transfer, the |
305 |
< |
* old table bin contains only a special forwarding node (with |
306 |
< |
* negative hash field) that contains the next table as its |
307 |
< |
* key. On encountering a forwarding node, access and update |
308 |
< |
* operations restart, using the new table. To ensure concurrent |
309 |
< |
* readability of traversals, transfers must proceed from the last |
310 |
< |
* bin (table.length - 1) up towards the first. Upon seeing a |
311 |
< |
* forwarding node, traversals (see class InternalIterator) |
312 |
< |
* arrange to move to the new table for the rest of the traversal |
313 |
< |
* without revisiting nodes. This constrains bin transfers to a |
314 |
< |
* particular order, and so can block indefinitely waiting for the |
315 |
< |
* next lock, and other threads cannot help with the transfer. |
316 |
< |
* However, expected stalls are infrequent enough to not warrant |
317 |
< |
* the additional overhead of access and iteration schemes that |
318 |
< |
* could admit out-of-order or concurrent bin transfers. |
291 |
> |
* parameter of about 0.5 on average, given the resizing threshold |
292 |
> |
* of 0.75, although with a large variance because of resizing |
293 |
> |
* granularity. Ignoring variance, the expected occurrences of |
294 |
> |
* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The |
295 |
> |
* first values are: |
296 |
> |
* |
297 |
> |
* 0: 0.60653066 |
298 |
> |
* 1: 0.30326533 |
299 |
> |
* 2: 0.07581633 |
300 |
> |
* 3: 0.01263606 |
301 |
> |
* 4: 0.00157952 |
302 |
> |
* 5: 0.00015795 |
303 |
> |
* 6: 0.00001316 |
304 |
> |
* 7: 0.00000094 |
305 |
> |
* 8: 0.00000006 |
306 |
> |
* more: less than 1 in ten million |
307 |
> |
* |
308 |
> |
* Lock contention probability for two threads accessing distinct |
309 |
> |
* elements is roughly 1 / (8 * #elements) under random hashes. |
310 |
> |
* |
311 |
> |
* Actual hash code distributions encountered in practice |
312 |
> |
* sometimes deviate significantly from uniform randomness. This |
313 |
> |
* includes the case when N > (1<<30), so some keys MUST collide. |
314 |
> |
* Similarly for dumb or hostile usages in which multiple keys are |
315 |
> |
* designed to have identical hash codes. Also, although we guard |
316 |
> |
* against the worst effects of this (see method spread), sets of |
317 |
> |
* hashes may differ only in bits that do not impact their bin |
318 |
> |
* index for a given power-of-two mask. So we use a secondary |
319 |
> |
* strategy that applies when the number of nodes in a bin exceeds |
320 |
> |
* a threshold, and at least one of the keys implements |
321 |
> |
* Comparable. These TreeBins use a balanced tree to hold nodes |
322 |
> |
* (a specialized form of red-black trees), bounding search time |
323 |
> |
* to O(log N). Each search step in a TreeBin is around twice as |
324 |
> |
* slow as in a regular list, but given that N cannot exceed |
325 |
> |
* (1<<64) (before running out of addresses) this bounds search |
326 |
> |
* steps, lock hold times, etc, to reasonable constants (roughly |
327 |
> |
* 100 nodes inspected per operation worst case) so long as keys |
328 |
> |
* are Comparable (which is very common -- String, Long, etc). |
329 |
> |
* TreeBin nodes (TreeNodes) also maintain the same "next" |
330 |
> |
* traversal pointers as regular nodes, so can be traversed in |
331 |
> |
* iterators in the same way. |
332 |
> |
* |
333 |
> |
* The table is resized when occupancy exceeds a percentage |
334 |
> |
* threshold (nominally, 0.75, but see below). Only a single |
335 |
> |
* thread performs the resize (using field "sizeCtl", to arrange |
336 |
> |
* exclusion), but the table otherwise remains usable for reads |
337 |
> |
* and updates. Resizing proceeds by transferring bins, one by |
338 |
> |
* one, from the table to the next table. Because we are using |
339 |
> |
* power-of-two expansion, the elements from each bin must either |
340 |
> |
* stay at same index, or move with a power of two offset. We |
341 |
> |
* eliminate unnecessary node creation by catching cases where old |
342 |
> |
* nodes can be reused because their next fields won't change. On |
343 |
> |
* average, only about one-sixth of them need cloning when a table |
344 |
> |
* doubles. The nodes they replace will be garbage collectable as |
345 |
> |
* soon as they are no longer referenced by any reader thread that |
346 |
> |
* may be in the midst of concurrently traversing table. Upon |
347 |
> |
* transfer, the old table bin contains only a special forwarding |
348 |
> |
* node (with hash field "MOVED") that contains the next table as |
349 |
> |
* its key. On encountering a forwarding node, access and update |
350 |
> |
* operations restart, using the new table. |
351 |
> |
* |
352 |
> |
* Each bin transfer requires its bin lock. However, unlike other |
353 |
> |
* cases, a transfer can skip a bin if it fails to acquire its |
354 |
> |
* lock, and revisit it later (unless it is a TreeBin). Method |
355 |
> |
* rebuild maintains a buffer of TRANSFER_BUFFER_SIZE bins that |
356 |
> |
* have been skipped because of failure to acquire a lock, and |
357 |
> |
* blocks only if none are available (i.e., only very rarely). |
358 |
> |
* The transfer operation must also ensure that all accessible |
359 |
> |
* bins in both the old and new table are usable by any traversal. |
360 |
> |
* When there are no lock acquisition failures, this is arranged |
361 |
> |
* simply by proceeding from the last bin (table.length - 1) up |
362 |
> |
* towards the first. Upon seeing a forwarding node, traversals |
363 |
> |
* (see class InternalIterator) arrange to move to the new table |
364 |
> |
* without revisiting nodes. However, when any node is skipped |
365 |
> |
* during a transfer, all earlier table bins may have become |
366 |
> |
* visible, so are initialized with a reverse-forwarding node back |
367 |
> |
* to the old table until the new ones are established. (This |
368 |
> |
* sometimes requires transiently locking a forwarding node, which |
369 |
> |
* is possible under the above encoding.) These more expensive |
370 |
> |
* mechanics trigger only when necessary. |
371 |
|
* |
372 |
< |
* This traversal scheme also applies to partial traversals of |
372 |
> |
* The traversal scheme also applies to partial traversals of |
373 |
|
* ranges of bins (via an alternate InternalIterator constructor) |
374 |
< |
* to support partitioned aggregate operations (that are not |
375 |
< |
* otherwise implemented yet). Also, read-only operations give up |
376 |
< |
* if ever forwarded to a null table, which provides support for |
377 |
< |
* shutdown-style clearing, which is also not currently |
194 |
< |
* implemented. |
374 |
> |
* to support partitioned aggregate operations. Also, read-only |
375 |
> |
* operations give up if ever forwarded to a null table, which |
376 |
> |
* provides support for shutdown-style clearing, which is also not |
377 |
> |
* currently implemented. |
378 |
|
* |
379 |
|
* Lazy table initialization minimizes footprint until first use, |
380 |
|
* and also avoids resizings when the first operation is from a |
381 |
|
* putAll, constructor with map argument, or deserialization. |
382 |
< |
* These cases attempt to override the targetCapacity used in |
383 |
< |
* growTable (which may harmlessly fail to take effect in cases of |
201 |
< |
* races with other ongoing resizings). |
382 |
> |
* These cases attempt to override the initial capacity settings, |
383 |
> |
* but harmlessly fail to take effect in cases of races. |
384 |
|
* |
385 |
|
* The element count is maintained using a LongAdder, which avoids |
386 |
|
* contention on updates but can encounter cache thrashing if read |
387 |
|
* too frequently during concurrent access. To avoid reading so |
388 |
< |
* often, resizing is normally attempted only upon adding to a bin |
389 |
< |
* already holding two or more nodes. Under the default load |
390 |
< |
* factor and uniform hash distributions, the probability of this |
391 |
< |
* occurring at threshold is around 13%, meaning that only about 1 |
392 |
< |
* in 8 puts check threshold (and after resizing, many fewer do |
393 |
< |
* so). But this approximation has high variance for small table |
394 |
< |
* sizes, so we check on any collision for sizes <= 64. Further, |
395 |
< |
* to increase the probability that a resize occurs soon enough, |
396 |
< |
* we offset the threshold (see THRESHOLD_OFFSET) by the expected |
397 |
< |
* number of puts between checks. This is currently set to 8, in |
398 |
< |
* accord with the default load factor. In practice, this default |
217 |
< |
* is rarely overridden, and in any case is close enough to other |
218 |
< |
* plausible values not to waste dynamic probability computation |
219 |
< |
* for the sake of more precision. |
388 |
> |
* often, resizing is attempted either when a bin lock is |
389 |
> |
* contended, or upon adding to a bin already holding two or more |
390 |
> |
* nodes (checked before adding in the xIfAbsent methods, after |
391 |
> |
* adding in others). Under uniform hash distributions, the |
392 |
> |
* probability of this occurring at threshold is around 13%, |
393 |
> |
* meaning that only about 1 in 8 puts check threshold (and after |
394 |
> |
* resizing, many fewer do so). But this approximation has high |
395 |
> |
* variance for small table sizes, so we check on any collision |
396 |
> |
* for sizes <= 64. The bulk putAll operation further reduces |
397 |
> |
* contention by only committing count updates upon these size |
398 |
> |
* checks. |
399 |
|
* |
400 |
|
* Maintaining API and serialization compatibility with previous |
401 |
|
* versions of this class introduces several oddities. Mainly: We |
402 |
|
* leave untouched but unused constructor arguments refering to |
403 |
< |
* concurrencyLevel. We also declare an unused "Segment" class |
404 |
< |
* that is instantiated in minimal form only when serializing. |
403 |
> |
* concurrencyLevel. We accept a loadFactor constructor argument, |
404 |
> |
* but apply it only to initial table capacity (which is the only |
405 |
> |
* time that we can guarantee to honor it.) We also declare an |
406 |
> |
* unused "Segment" class that is instantiated in minimal form |
407 |
> |
* only when serializing. |
408 |
|
*/ |
409 |
|
|
410 |
|
/* ---------------- Constants -------------- */ |
411 |
|
|
412 |
|
/** |
413 |
< |
* The largest allowed table capacity. Must be a power of 2, at |
414 |
< |
* most 1<<30 to stay within Java array size limits. |
413 |
> |
* The largest possible table capacity. This value must be |
414 |
> |
* exactly 1<<30 to stay within Java array allocation and indexing |
415 |
> |
* bounds for power of two table sizes, and is further required |
416 |
> |
* because the top two bits of 32bit hash fields are used for |
417 |
> |
* control purposes. |
418 |
|
*/ |
419 |
|
private static final int MAXIMUM_CAPACITY = 1 << 30; |
420 |
|
|
425 |
|
private static final int DEFAULT_CAPACITY = 16; |
426 |
|
|
427 |
|
/** |
428 |
< |
* The default load factor for this table, used when not otherwise |
429 |
< |
* specified in a constructor. |
428 |
> |
* The largest possible (non-power of two) array size. |
429 |
> |
* Needed by toArray and related methods. |
430 |
|
*/ |
431 |
< |
private static final float DEFAULT_LOAD_FACTOR = 0.75f; |
431 |
> |
static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; |
432 |
|
|
433 |
|
/** |
434 |
< |
* The default concurrency level for this table. Unused, but |
434 |
> |
* The default concurrency level for this table. Unused but |
435 |
|
* defined for compatibility with previous versions of this class. |
436 |
|
*/ |
437 |
|
private static final int DEFAULT_CONCURRENCY_LEVEL = 16; |
438 |
|
|
439 |
|
/** |
440 |
< |
* The count value to offset thresholds to compensate for checking |
441 |
< |
* for the need to resize only when inserting into bins with two |
442 |
< |
* or more elements. See above for explanation. |
440 |
> |
* The load factor for this table. Overrides of this value in |
441 |
> |
* constructors affect only the initial table capacity. The |
442 |
> |
* actual floating point value isn't normally used -- it is |
443 |
> |
* simpler to use expressions such as {@code n - (n >>> 2)} for |
444 |
> |
* the associated resizing threshold. |
445 |
|
*/ |
446 |
< |
private static final int THRESHOLD_OFFSET = 8; |
260 |
< |
|
261 |
< |
/* ---------------- Nodes -------------- */ |
446 |
> |
private static final float LOAD_FACTOR = 0.75f; |
447 |
|
|
448 |
|
/** |
449 |
< |
* Key-value entry. Note that this is never exported out as a |
450 |
< |
* user-visible Map.Entry. Nodes with a negative hash field are |
451 |
< |
* special, and do not contain user keys or values. Otherwise, |
267 |
< |
* keys are never null, and null val fields indicate that a node |
268 |
< |
* is in the process of being deleted or created. For purposes of |
269 |
< |
* read-only, access, a key may be read before a val, but can only |
270 |
< |
* be used after checking val. (For an update operation, when a |
271 |
< |
* lock is held on a node, order doesn't matter.) |
449 |
> |
* The buffer size for skipped bins during transfers. The |
450 |
> |
* value is arbitrary but should be large enough to avoid |
451 |
> |
* most locking stalls during resizes. |
452 |
|
*/ |
453 |
< |
static final class Node { |
274 |
< |
final int hash; |
275 |
< |
final Object key; |
276 |
< |
volatile Object val; |
277 |
< |
volatile Node next; |
278 |
< |
|
279 |
< |
Node(int hash, Object key, Object val, Node next) { |
280 |
< |
this.hash = hash; |
281 |
< |
this.key = key; |
282 |
< |
this.val = val; |
283 |
< |
this.next = next; |
284 |
< |
} |
285 |
< |
} |
453 |
> |
private static final int TRANSFER_BUFFER_SIZE = 32; |
454 |
|
|
455 |
|
/** |
456 |
< |
* Sign bit of node hash value indicating to use table in node.key. |
456 |
> |
* The bin count threshold for using a tree rather than list for a |
457 |
> |
* bin. The value reflects the approximate break-even point for |
458 |
> |
* using tree-based operations. |
459 |
|
*/ |
460 |
< |
private static final int SIGN_BIT = 0x80000000; |
460 |
> |
private static final int TREE_THRESHOLD = 8; |
461 |
> |
|
462 |
> |
/* |
463 |
> |
* Encodings for special uses of Node hash fields. See above for |
464 |
> |
* explanation. |
465 |
> |
*/ |
466 |
> |
static final int MOVED = 0x80000000; // hash field for forwarding nodes |
467 |
> |
static final int LOCKED = 0x40000000; // set/tested only as a bit |
468 |
> |
static final int WAITING = 0xc0000000; // both bits set/tested together |
469 |
> |
static final int HASH_BITS = 0x3fffffff; // usable bits of normal node hash |
470 |
|
|
471 |
|
/* ---------------- Fields -------------- */ |
472 |
|
|
476 |
|
*/ |
477 |
|
transient volatile Node[] table; |
478 |
|
|
479 |
< |
/** The counter maintaining number of elements. */ |
479 |
> |
/** |
480 |
> |
* The counter maintaining number of elements. |
481 |
> |
*/ |
482 |
|
private transient final LongAdder counter; |
483 |
< |
/** Nonzero when table is being initialized or resized. Updated via CAS. */ |
484 |
< |
private transient volatile int resizing; |
485 |
< |
/** The next element count value upon which to resize the table. */ |
486 |
< |
private transient int threshold; |
487 |
< |
/** The target capacity; volatile to cover initialization races. */ |
488 |
< |
private transient volatile int targetCapacity; |
489 |
< |
/** The target load factor for the table */ |
490 |
< |
private transient final float loadFactor; |
483 |
> |
|
484 |
> |
/** |
485 |
> |
* Table initialization and resizing control. When negative, the |
486 |
> |
* table is being initialized or resized. Otherwise, when table is |
487 |
> |
* null, holds the initial table size to use upon creation, or 0 |
488 |
> |
* for default. After initialization, holds the next element count |
489 |
> |
* value upon which to resize the table. |
490 |
> |
*/ |
491 |
> |
private transient volatile int sizeCtl; |
492 |
|
|
493 |
|
// views |
494 |
|
private transient KeySet<K,V> keySet; |
524 |
|
UNSAFE.putObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE, v); |
525 |
|
} |
526 |
|
|
527 |
< |
/* ----------------Table Initialization and Resizing -------------- */ |
527 |
> |
/* ---------------- Nodes -------------- */ |
528 |
|
|
529 |
|
/** |
530 |
< |
* Returns a power of two table size for the given desired capacity. |
531 |
< |
* See Hackers Delight, sec 3.2 |
530 |
> |
* Key-value entry. Note that this is never exported out as a |
531 |
> |
* user-visible Map.Entry (see MapEntry below). Nodes with a hash |
532 |
> |
* field of MOVED are special, and do not contain user keys or |
533 |
> |
* values. Otherwise, keys are never null, and null val fields |
534 |
> |
* indicate that a node is in the process of being deleted or |
535 |
> |
* created. For purposes of read-only access, a key may be read |
536 |
> |
* before a val, but can only be used after checking val to be |
537 |
> |
* non-null. |
538 |
|
*/ |
539 |
< |
private static final int tableSizeFor(int c) { |
540 |
< |
int n = c - 1; |
541 |
< |
n |= n >>> 1; |
542 |
< |
n |= n >>> 2; |
543 |
< |
n |= n >>> 4; |
356 |
< |
n |= n >>> 8; |
357 |
< |
n |= n >>> 16; |
358 |
< |
return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1; |
359 |
< |
} |
539 |
> |
static class Node { |
540 |
> |
volatile int hash; |
541 |
> |
final Object key; |
542 |
> |
volatile Object val; |
543 |
> |
volatile Node next; |
544 |
|
|
545 |
< |
/** |
546 |
< |
* If not already resizing, initializes or creates next table and |
547 |
< |
* transfers bins. Initial table size uses the capacity recorded |
548 |
< |
* in targetCapacity. Rechecks occupancy after a transfer to see |
549 |
< |
* if another resize is already needed because resizings are |
550 |
< |
* lagging additions. |
551 |
< |
* |
552 |
< |
* @return current table |
553 |
< |
*/ |
554 |
< |
private final Node[] growTable() { |
555 |
< |
if (resizing == 0 && |
556 |
< |
UNSAFE.compareAndSwapInt(this, resizingOffset, 0, 1)) { |
557 |
< |
try { |
558 |
< |
for (;;) { |
559 |
< |
Node[] tab = table; |
560 |
< |
int n, c; |
561 |
< |
if (tab == null) |
562 |
< |
n = (c = targetCapacity) > 0 ? c : DEFAULT_CAPACITY; |
563 |
< |
else if ((n = tab.length) < MAXIMUM_CAPACITY && |
564 |
< |
counter.sum() >= threshold) |
565 |
< |
n <<= 1; |
566 |
< |
else |
567 |
< |
break; |
568 |
< |
Node[] nextTab = new Node[n]; |
569 |
< |
threshold = (int)(n * loadFactor) - THRESHOLD_OFFSET; |
570 |
< |
if (tab != null) |
571 |
< |
transfer(tab, nextTab, |
572 |
< |
new Node(SIGN_BIT, nextTab, null, null)); |
573 |
< |
table = nextTab; |
574 |
< |
if (tab == null) |
545 |
> |
Node(int hash, Object key, Object val, Node next) { |
546 |
> |
this.hash = hash; |
547 |
> |
this.key = key; |
548 |
> |
this.val = val; |
549 |
> |
this.next = next; |
550 |
> |
} |
551 |
> |
|
552 |
> |
/** CompareAndSet the hash field */ |
553 |
> |
final boolean casHash(int cmp, int val) { |
554 |
> |
return UNSAFE.compareAndSwapInt(this, hashOffset, cmp, val); |
555 |
> |
} |
556 |
> |
|
557 |
> |
/** The number of spins before blocking for a lock */ |
558 |
> |
static final int MAX_SPINS = |
559 |
> |
Runtime.getRuntime().availableProcessors() > 1 ? 64 : 1; |
560 |
> |
|
561 |
> |
/** |
562 |
> |
* Spins a while if LOCKED bit set and this node is the first |
563 |
> |
* of its bin, and then sets WAITING bits on hash field and |
564 |
> |
* blocks (once) if they are still set. It is OK for this |
565 |
> |
* method to return even if lock is not available upon exit, |
566 |
> |
* which enables these simple single-wait mechanics. |
567 |
> |
* |
568 |
> |
* The corresponding signalling operation is performed within |
569 |
> |
* callers: Upon detecting that WAITING has been set when |
570 |
> |
* unlocking lock (via a failed CAS from non-waiting LOCKED |
571 |
> |
* state), unlockers acquire the sync lock and perform a |
572 |
> |
* notifyAll. |
573 |
> |
*/ |
574 |
> |
final void tryAwaitLock(Node[] tab, int i) { |
575 |
> |
if (tab != null && i >= 0 && i < tab.length) { // bounds check |
576 |
> |
int r = ThreadLocalRandom.current().nextInt(); // randomize spins |
577 |
> |
int spins = MAX_SPINS, h; |
578 |
> |
while (tabAt(tab, i) == this && ((h = hash) & LOCKED) != 0) { |
579 |
> |
if (spins >= 0) { |
580 |
> |
r ^= r << 1; r ^= r >>> 3; r ^= r << 10; // xorshift |
581 |
> |
if (r >= 0 && --spins == 0) |
582 |
> |
Thread.yield(); // yield before block |
583 |
> |
} |
584 |
> |
else if (casHash(h, h | WAITING)) { |
585 |
> |
synchronized (this) { |
586 |
> |
if (tabAt(tab, i) == this && |
587 |
> |
(hash & WAITING) == WAITING) { |
588 |
> |
try { |
589 |
> |
wait(); |
590 |
> |
} catch (InterruptedException ie) { |
591 |
> |
Thread.currentThread().interrupt(); |
592 |
> |
} |
593 |
> |
} |
594 |
> |
else |
595 |
> |
notifyAll(); // possibly won race vs signaller |
596 |
> |
} |
597 |
|
break; |
598 |
+ |
} |
599 |
|
} |
393 |
– |
} finally { |
394 |
– |
resizing = 0; |
600 |
|
} |
601 |
|
} |
602 |
< |
else if (table == null) |
603 |
< |
Thread.yield(); // lost initialization race; just spin |
604 |
< |
return table; |
602 |
> |
|
603 |
> |
// Unsafe mechanics for casHash |
604 |
> |
private static final sun.misc.Unsafe UNSAFE; |
605 |
> |
private static final long hashOffset; |
606 |
> |
|
607 |
> |
static { |
608 |
> |
try { |
609 |
> |
UNSAFE = getUnsafe(); |
610 |
> |
Class<?> k = Node.class; |
611 |
> |
hashOffset = UNSAFE.objectFieldOffset |
612 |
> |
(k.getDeclaredField("hash")); |
613 |
> |
} catch (Exception e) { |
614 |
> |
throw new Error(e); |
615 |
> |
} |
616 |
> |
} |
617 |
|
} |
618 |
|
|
619 |
< |
/* |
620 |
< |
* Reclassifies nodes in each bin to new table. Because we are |
621 |
< |
* using power-of-two expansion, the elements from each bin must |
622 |
< |
* either stay at same index, or move with a power of two |
406 |
< |
* offset. We eliminate unnecessary node creation by catching |
407 |
< |
* cases where old nodes can be reused because their next fields |
408 |
< |
* won't change. Statistically, at the default loadFactor, only |
409 |
< |
* about one-sixth of them need cloning when a table doubles. The |
410 |
< |
* nodes they replace will be garbage collectable as soon as they |
411 |
< |
* are no longer referenced by any reader thread that may be in |
412 |
< |
* the midst of concurrently traversing table. |
413 |
< |
* |
414 |
< |
* Transfers are done from the bottom up to preserve iterator |
415 |
< |
* traversability. On each step, the old bin is locked, |
416 |
< |
* moved/copied, and then replaced with a forwarding node. |
619 |
> |
/* ---------------- TreeBins -------------- */ |
620 |
> |
|
621 |
> |
/** |
622 |
> |
* Nodes for use in TreeBins |
623 |
|
*/ |
624 |
< |
private static final void transfer(Node[] tab, Node[] nextTab, Node fwd) { |
625 |
< |
int n = tab.length; |
626 |
< |
Node ignore = nextTab[n + n - 1]; // force bounds check |
627 |
< |
for (int i = n - 1; i >= 0; --i) { |
628 |
< |
for (Node e;;) { |
629 |
< |
if ((e = tabAt(tab, i)) != null) { |
630 |
< |
boolean validated = false; |
631 |
< |
synchronized (e) { |
632 |
< |
if (tabAt(tab, i) == e) { |
633 |
< |
validated = true; |
634 |
< |
Node lo = null, hi = null, lastRun = e; |
635 |
< |
int runBit = e.hash & n; |
636 |
< |
for (Node p = e.next; p != null; p = p.next) { |
637 |
< |
int b = p.hash & n; |
638 |
< |
if (b != runBit) { |
639 |
< |
runBit = b; |
640 |
< |
lastRun = p; |
624 |
> |
static final class TreeNode extends Node { |
625 |
> |
TreeNode parent; // red-black tree links |
626 |
> |
TreeNode left; |
627 |
> |
TreeNode right; |
628 |
> |
TreeNode prev; // needed to unlink next upon deletion |
629 |
> |
boolean red; |
630 |
> |
|
631 |
> |
TreeNode(int hash, Object key, Object val, Node next, TreeNode parent) { |
632 |
> |
super(hash, key, val, next); |
633 |
> |
this.parent = parent; |
634 |
> |
} |
635 |
> |
} |
636 |
> |
|
637 |
> |
/** |
638 |
> |
* A specialized form of red-black tree for use in bins |
639 |
> |
* whose size exceeds a threshold. |
640 |
> |
* |
641 |
> |
* TreeBins use a special form of comparison for search and |
642 |
> |
* related operations (which is the main reason we cannot use |
643 |
> |
* existing collections such as TreeMaps). TreeBins contain |
644 |
> |
* Comparable elements, but may contain others, as well as |
645 |
> |
* elements that are Comparable but not necessarily Comparable<T> |
646 |
> |
* for the same T, so we cannot invoke compareTo among them. To |
647 |
> |
* handle this, the tree is ordered primarily by hash value, then |
648 |
> |
* by getClass().getName() order, and then by Comparator order |
649 |
> |
* among elements of the same class. On lookup at a node, if |
650 |
> |
* elements are not comparable or compare as 0, both left and |
651 |
> |
* right children may need to be searched in the case of tied hash |
652 |
> |
* values. (This corresponds to the full list search that would be |
653 |
> |
* necessary if all elements were non-Comparable and had tied |
654 |
> |
* hashes.) The red-black balancing code is updated from |
655 |
> |
* pre-jdk-collections |
656 |
> |
* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java) |
657 |
> |
* based in turn on Cormen, Leiserson, and Rivest "Introduction to |
658 |
> |
* Algorithms" (CLR). |
659 |
> |
* |
660 |
> |
* TreeBins also maintain a separate locking discipline than |
661 |
> |
* regular bins. Because they are forwarded via special MOVED |
662 |
> |
* nodes at bin heads (which can never change once established), |
663 |
> |
* we cannot use use those nodes as locks. Instead, TreeBin |
664 |
> |
* extends AbstractQueuedSynchronizer to support a simple form of |
665 |
> |
* read-write lock. For update operations and table validation, |
666 |
> |
* the exclusive form of lock behaves in the same way as bin-head |
667 |
> |
* locks. However, lookups use shared read-lock mechanics to allow |
668 |
> |
* multiple readers in the absence of writers. Additionally, |
669 |
> |
* these lookups do not ever block: While the lock is not |
670 |
> |
* available, they proceed along the slow traversal path (via |
671 |
> |
* next-pointers) until the lock becomes available or the list is |
672 |
> |
* exhausted, whichever comes first. (These cases are not fast, |
673 |
> |
* but maximize aggregate expected throughput.) The AQS mechanics |
674 |
> |
* for doing this are straightforward. The lock state is held as |
675 |
> |
* AQS getState(). Read counts are negative; the write count (1) |
676 |
> |
* is positive. There are no signalling preferences among readers |
677 |
> |
* and writers. Since we don't need to export full Lock API, we |
678 |
> |
* just override the minimal AQS methods and use them directly. |
679 |
> |
*/ |
680 |
> |
static final class TreeBin extends AbstractQueuedSynchronizer { |
681 |
> |
private static final long serialVersionUID = 2249069246763182397L; |
682 |
> |
transient TreeNode root; // root of tree |
683 |
> |
transient TreeNode first; // head of next-pointer list |
684 |
> |
|
685 |
> |
/* AQS overrides */ |
686 |
> |
public final boolean isHeldExclusively() { return getState() > 0; } |
687 |
> |
public final boolean tryAcquire(int ignore) { |
688 |
> |
if (compareAndSetState(0, 1)) { |
689 |
> |
setExclusiveOwnerThread(Thread.currentThread()); |
690 |
> |
return true; |
691 |
> |
} |
692 |
> |
return false; |
693 |
> |
} |
694 |
> |
public final boolean tryRelease(int ignore) { |
695 |
> |
setExclusiveOwnerThread(null); |
696 |
> |
setState(0); |
697 |
> |
return true; |
698 |
> |
} |
699 |
> |
public final int tryAcquireShared(int ignore) { |
700 |
> |
for (int c;;) { |
701 |
> |
if ((c = getState()) > 0) |
702 |
> |
return -1; |
703 |
> |
if (compareAndSetState(c, c -1)) |
704 |
> |
return 1; |
705 |
> |
} |
706 |
> |
} |
707 |
> |
public final boolean tryReleaseShared(int ignore) { |
708 |
> |
int c; |
709 |
> |
do {} while (!compareAndSetState(c = getState(), c + 1)); |
710 |
> |
return c == -1; |
711 |
> |
} |
712 |
> |
|
713 |
> |
/** From CLR */ |
714 |
> |
private void rotateLeft(TreeNode p) { |
715 |
> |
if (p != null) { |
716 |
> |
TreeNode r = p.right, pp, rl; |
717 |
> |
if ((rl = p.right = r.left) != null) |
718 |
> |
rl.parent = p; |
719 |
> |
if ((pp = r.parent = p.parent) == null) |
720 |
> |
root = r; |
721 |
> |
else if (pp.left == p) |
722 |
> |
pp.left = r; |
723 |
> |
else |
724 |
> |
pp.right = r; |
725 |
> |
r.left = p; |
726 |
> |
p.parent = r; |
727 |
> |
} |
728 |
> |
} |
729 |
> |
|
730 |
> |
/** From CLR */ |
731 |
> |
private void rotateRight(TreeNode p) { |
732 |
> |
if (p != null) { |
733 |
> |
TreeNode l = p.left, pp, lr; |
734 |
> |
if ((lr = p.left = l.right) != null) |
735 |
> |
lr.parent = p; |
736 |
> |
if ((pp = l.parent = p.parent) == null) |
737 |
> |
root = l; |
738 |
> |
else if (pp.right == p) |
739 |
> |
pp.right = l; |
740 |
> |
else |
741 |
> |
pp.left = l; |
742 |
> |
l.right = p; |
743 |
> |
p.parent = l; |
744 |
> |
} |
745 |
> |
} |
746 |
> |
|
747 |
> |
/** |
748 |
> |
* Return the TreeNode (or null if not found) for the given key |
749 |
> |
* starting at given root. |
750 |
> |
*/ |
751 |
> |
@SuppressWarnings("unchecked") // suppress Comparable cast warning |
752 |
> |
final TreeNode getTreeNode(int h, Object k, TreeNode p) { |
753 |
> |
Class<?> c = k.getClass(); |
754 |
> |
while (p != null) { |
755 |
> |
int dir, ph; Object pk; Class<?> pc; |
756 |
> |
if ((ph = p.hash) == h) { |
757 |
> |
if ((pk = p.key) == k || k.equals(pk)) |
758 |
> |
return p; |
759 |
> |
if (c != (pc = pk.getClass()) || |
760 |
> |
!(k instanceof Comparable) || |
761 |
> |
(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) { |
762 |
> |
dir = (c == pc)? 0 : c.getName().compareTo(pc.getName()); |
763 |
> |
TreeNode r = null, s = null, pl, pr; |
764 |
> |
if (dir >= 0) { |
765 |
> |
if ((pl = p.left) != null && h <= pl.hash) |
766 |
> |
s = pl; |
767 |
> |
} |
768 |
> |
else if ((pr = p.right) != null && h >= pr.hash) |
769 |
> |
s = pr; |
770 |
> |
if (s != null && (r = getTreeNode(h, k, s)) != null) |
771 |
> |
return r; |
772 |
> |
} |
773 |
> |
} |
774 |
> |
else |
775 |
> |
dir = (h < ph) ? -1 : 1; |
776 |
> |
p = (dir > 0) ? p.right : p.left; |
777 |
> |
} |
778 |
> |
return null; |
779 |
> |
} |
780 |
> |
|
781 |
> |
/** |
782 |
> |
* Wrapper for getTreeNode used by CHM.get. Tries to obtain |
783 |
> |
* read-lock to call getTreeNode, but during failure to get |
784 |
> |
* lock, searches along next links. |
785 |
> |
*/ |
786 |
> |
final Object getValue(int h, Object k) { |
787 |
> |
Node r = null; |
788 |
> |
int c = getState(); // Must read lock state first |
789 |
> |
for (Node e = first; e != null; e = e.next) { |
790 |
> |
if (c <= 0 && compareAndSetState(c, c - 1)) { |
791 |
> |
try { |
792 |
> |
r = getTreeNode(h, k, root); |
793 |
> |
} finally { |
794 |
> |
releaseShared(0); |
795 |
> |
} |
796 |
> |
break; |
797 |
> |
} |
798 |
> |
else if ((e.hash & HASH_BITS) == h && k.equals(e.key)) { |
799 |
> |
r = e; |
800 |
> |
break; |
801 |
> |
} |
802 |
> |
else |
803 |
> |
c = getState(); |
804 |
> |
} |
805 |
> |
return r == null ? null : r.val; |
806 |
> |
} |
807 |
> |
|
808 |
> |
/** |
809 |
> |
* Find or add a node |
810 |
> |
* @return null if added |
811 |
> |
*/ |
812 |
> |
@SuppressWarnings("unchecked") // suppress Comparable cast warning |
813 |
> |
final TreeNode putTreeNode(int h, Object k, Object v) { |
814 |
> |
Class<?> c = k.getClass(); |
815 |
> |
TreeNode pp = root, p = null; |
816 |
> |
int dir = 0; |
817 |
> |
while (pp != null) { // find existing node or leaf to insert at |
818 |
> |
int ph; Object pk; Class<?> pc; |
819 |
> |
p = pp; |
820 |
> |
if ((ph = p.hash) == h) { |
821 |
> |
if ((pk = p.key) == k || k.equals(pk)) |
822 |
> |
return p; |
823 |
> |
if (c != (pc = pk.getClass()) || |
824 |
> |
!(k instanceof Comparable) || |
825 |
> |
(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) { |
826 |
> |
dir = (c == pc)? 0 : c.getName().compareTo(pc.getName()); |
827 |
> |
TreeNode r = null, s = null, pl, pr; |
828 |
> |
if (dir >= 0) { |
829 |
> |
if ((pl = p.left) != null && h <= pl.hash) |
830 |
> |
s = pl; |
831 |
> |
} |
832 |
> |
else if ((pr = p.right) != null && h >= pr.hash) |
833 |
> |
s = pr; |
834 |
> |
if (s != null && (r = getTreeNode(h, k, s)) != null) |
835 |
> |
return r; |
836 |
> |
} |
837 |
> |
} |
838 |
> |
else |
839 |
> |
dir = (h < ph) ? -1 : 1; |
840 |
> |
pp = (dir > 0) ? p.right : p.left; |
841 |
> |
} |
842 |
> |
|
843 |
> |
TreeNode f = first; |
844 |
> |
TreeNode x = first = new TreeNode(h, k, v, f, p); |
845 |
> |
if (p == null) |
846 |
> |
root = x; |
847 |
> |
else { // attach and rebalance; adapted from CLR |
848 |
> |
TreeNode xp, xpp; |
849 |
> |
if (f != null) |
850 |
> |
f.prev = x; |
851 |
> |
if (dir <= 0) |
852 |
> |
p.left = x; |
853 |
> |
else |
854 |
> |
p.right = x; |
855 |
> |
x.red = true; |
856 |
> |
while (x != null && (xp = x.parent) != null && xp.red && |
857 |
> |
(xpp = xp.parent) != null) { |
858 |
> |
TreeNode xppl = xpp.left; |
859 |
> |
if (xp == xppl) { |
860 |
> |
TreeNode y = xpp.right; |
861 |
> |
if (y != null && y.red) { |
862 |
> |
y.red = false; |
863 |
> |
xp.red = false; |
864 |
> |
xpp.red = true; |
865 |
> |
x = xpp; |
866 |
> |
} |
867 |
> |
else { |
868 |
> |
if (x == xp.right) { |
869 |
> |
rotateLeft(x = xp); |
870 |
> |
xpp = (xp = x.parent) == null ? null : xp.parent; |
871 |
> |
} |
872 |
> |
if (xp != null) { |
873 |
> |
xp.red = false; |
874 |
> |
if (xpp != null) { |
875 |
> |
xpp.red = true; |
876 |
> |
rotateRight(xpp); |
877 |
|
} |
878 |
|
} |
879 |
< |
if (runBit == 0) |
880 |
< |
lo = lastRun; |
881 |
< |
else |
882 |
< |
hi = lastRun; |
883 |
< |
for (Node p = e; p != lastRun; p = p.next) { |
884 |
< |
int ph = p.hash; |
885 |
< |
Object pk = p.key, pv = p.val; |
886 |
< |
if ((ph & n) == 0) |
887 |
< |
lo = new Node(ph, pk, pv, lo); |
888 |
< |
else |
889 |
< |
hi = new Node(ph, pk, pv, hi); |
879 |
> |
} |
880 |
> |
} |
881 |
> |
else { |
882 |
> |
TreeNode y = xppl; |
883 |
> |
if (y != null && y.red) { |
884 |
> |
y.red = false; |
885 |
> |
xp.red = false; |
886 |
> |
xpp.red = true; |
887 |
> |
x = xpp; |
888 |
> |
} |
889 |
> |
else { |
890 |
> |
if (x == xp.left) { |
891 |
> |
rotateRight(x = xp); |
892 |
> |
xpp = (xp = x.parent) == null ? null : xp.parent; |
893 |
> |
} |
894 |
> |
if (xp != null) { |
895 |
> |
xp.red = false; |
896 |
> |
if (xpp != null) { |
897 |
> |
xpp.red = true; |
898 |
> |
rotateLeft(xpp); |
899 |
> |
} |
900 |
|
} |
449 |
– |
setTabAt(nextTab, i, lo); |
450 |
– |
setTabAt(nextTab, i + n, hi); |
451 |
– |
setTabAt(tab, i, fwd); |
901 |
|
} |
902 |
|
} |
903 |
< |
if (validated) |
903 |
> |
} |
904 |
> |
TreeNode r = root; |
905 |
> |
if (r != null && r.red) |
906 |
> |
r.red = false; |
907 |
> |
} |
908 |
> |
return null; |
909 |
> |
} |
910 |
> |
|
911 |
> |
/** |
912 |
> |
* Removes the given node, that must be present before this |
913 |
> |
* call. This is messier than typical red-black deletion code |
914 |
> |
* because we cannot swap the contents of an interior node |
915 |
> |
* with a leaf successor that is pinned by "next" pointers |
916 |
> |
* that are accessible independently of lock. So instead we |
917 |
> |
* swap the tree linkages. |
918 |
> |
*/ |
919 |
> |
final void deleteTreeNode(TreeNode p) { |
920 |
> |
TreeNode next = (TreeNode)p.next; // unlink traversal pointers |
921 |
> |
TreeNode pred = p.prev; |
922 |
> |
if (pred == null) |
923 |
> |
first = next; |
924 |
> |
else |
925 |
> |
pred.next = next; |
926 |
> |
if (next != null) |
927 |
> |
next.prev = pred; |
928 |
> |
TreeNode replacement; |
929 |
> |
TreeNode pl = p.left; |
930 |
> |
TreeNode pr = p.right; |
931 |
> |
if (pl != null && pr != null) { |
932 |
> |
TreeNode s = pr, sl; |
933 |
> |
while ((sl = s.left) != null) // find successor |
934 |
> |
s = sl; |
935 |
> |
boolean c = s.red; s.red = p.red; p.red = c; // swap colors |
936 |
> |
TreeNode sr = s.right; |
937 |
> |
TreeNode pp = p.parent; |
938 |
> |
if (s == pr) { // p was s's direct parent |
939 |
> |
p.parent = s; |
940 |
> |
s.right = p; |
941 |
> |
} |
942 |
> |
else { |
943 |
> |
TreeNode sp = s.parent; |
944 |
> |
if ((p.parent = sp) != null) { |
945 |
> |
if (s == sp.left) |
946 |
> |
sp.left = p; |
947 |
> |
else |
948 |
> |
sp.right = p; |
949 |
> |
} |
950 |
> |
if ((s.right = pr) != null) |
951 |
> |
pr.parent = s; |
952 |
> |
} |
953 |
> |
p.left = null; |
954 |
> |
if ((p.right = sr) != null) |
955 |
> |
sr.parent = p; |
956 |
> |
if ((s.left = pl) != null) |
957 |
> |
pl.parent = s; |
958 |
> |
if ((s.parent = pp) == null) |
959 |
> |
root = s; |
960 |
> |
else if (p == pp.left) |
961 |
> |
pp.left = s; |
962 |
> |
else |
963 |
> |
pp.right = s; |
964 |
> |
replacement = sr; |
965 |
> |
} |
966 |
> |
else |
967 |
> |
replacement = (pl != null) ? pl : pr; |
968 |
> |
TreeNode pp = p.parent; |
969 |
> |
if (replacement == null) { |
970 |
> |
if (pp == null) { |
971 |
> |
root = null; |
972 |
> |
return; |
973 |
> |
} |
974 |
> |
replacement = p; |
975 |
> |
} |
976 |
> |
else { |
977 |
> |
replacement.parent = pp; |
978 |
> |
if (pp == null) |
979 |
> |
root = replacement; |
980 |
> |
else if (p == pp.left) |
981 |
> |
pp.left = replacement; |
982 |
> |
else |
983 |
> |
pp.right = replacement; |
984 |
> |
p.left = p.right = p.parent = null; |
985 |
> |
} |
986 |
> |
if (!p.red) { // rebalance, from CLR |
987 |
> |
TreeNode x = replacement; |
988 |
> |
while (x != null) { |
989 |
> |
TreeNode xp, xpl; |
990 |
> |
if (x.red || (xp = x.parent) == null) { |
991 |
> |
x.red = false; |
992 |
|
break; |
993 |
+ |
} |
994 |
+ |
if (x == (xpl = xp.left)) { |
995 |
+ |
TreeNode sib = xp.right; |
996 |
+ |
if (sib != null && sib.red) { |
997 |
+ |
sib.red = false; |
998 |
+ |
xp.red = true; |
999 |
+ |
rotateLeft(xp); |
1000 |
+ |
sib = (xp = x.parent) == null ? null : xp.right; |
1001 |
+ |
} |
1002 |
+ |
if (sib == null) |
1003 |
+ |
x = xp; |
1004 |
+ |
else { |
1005 |
+ |
TreeNode sl = sib.left, sr = sib.right; |
1006 |
+ |
if ((sr == null || !sr.red) && |
1007 |
+ |
(sl == null || !sl.red)) { |
1008 |
+ |
sib.red = true; |
1009 |
+ |
x = xp; |
1010 |
+ |
} |
1011 |
+ |
else { |
1012 |
+ |
if (sr == null || !sr.red) { |
1013 |
+ |
if (sl != null) |
1014 |
+ |
sl.red = false; |
1015 |
+ |
sib.red = true; |
1016 |
+ |
rotateRight(sib); |
1017 |
+ |
sib = (xp = x.parent) == null ? null : xp.right; |
1018 |
+ |
} |
1019 |
+ |
if (sib != null) { |
1020 |
+ |
sib.red = (xp == null)? false : xp.red; |
1021 |
+ |
if ((sr = sib.right) != null) |
1022 |
+ |
sr.red = false; |
1023 |
+ |
} |
1024 |
+ |
if (xp != null) { |
1025 |
+ |
xp.red = false; |
1026 |
+ |
rotateLeft(xp); |
1027 |
+ |
} |
1028 |
+ |
x = root; |
1029 |
+ |
} |
1030 |
+ |
} |
1031 |
+ |
} |
1032 |
+ |
else { // symmetric |
1033 |
+ |
TreeNode sib = xpl; |
1034 |
+ |
if (sib != null && sib.red) { |
1035 |
+ |
sib.red = false; |
1036 |
+ |
xp.red = true; |
1037 |
+ |
rotateRight(xp); |
1038 |
+ |
sib = (xp = x.parent) == null ? null : xp.left; |
1039 |
+ |
} |
1040 |
+ |
if (sib == null) |
1041 |
+ |
x = xp; |
1042 |
+ |
else { |
1043 |
+ |
TreeNode sl = sib.left, sr = sib.right; |
1044 |
+ |
if ((sl == null || !sl.red) && |
1045 |
+ |
(sr == null || !sr.red)) { |
1046 |
+ |
sib.red = true; |
1047 |
+ |
x = xp; |
1048 |
+ |
} |
1049 |
+ |
else { |
1050 |
+ |
if (sl == null || !sl.red) { |
1051 |
+ |
if (sr != null) |
1052 |
+ |
sr.red = false; |
1053 |
+ |
sib.red = true; |
1054 |
+ |
rotateLeft(sib); |
1055 |
+ |
sib = (xp = x.parent) == null ? null : xp.left; |
1056 |
+ |
} |
1057 |
+ |
if (sib != null) { |
1058 |
+ |
sib.red = (xp == null)? false : xp.red; |
1059 |
+ |
if ((sl = sib.left) != null) |
1060 |
+ |
sl.red = false; |
1061 |
+ |
} |
1062 |
+ |
if (xp != null) { |
1063 |
+ |
xp.red = false; |
1064 |
+ |
rotateRight(xp); |
1065 |
+ |
} |
1066 |
+ |
x = root; |
1067 |
+ |
} |
1068 |
+ |
} |
1069 |
+ |
} |
1070 |
|
} |
1071 |
< |
else if (casTabAt(tab, i, e, fwd)) |
1072 |
< |
break; |
1071 |
> |
} |
1072 |
> |
if (p == replacement && (pp = p.parent) != null) { |
1073 |
> |
if (p == pp.left) // detach pointers |
1074 |
> |
pp.left = null; |
1075 |
> |
else if (p == pp.right) |
1076 |
> |
pp.right = null; |
1077 |
> |
p.parent = null; |
1078 |
|
} |
1079 |
|
} |
1080 |
|
} |
1081 |
|
|
1082 |
< |
/* ---------------- Internal access and update methods -------------- */ |
1082 |
> |
/* ---------------- Collision reduction methods -------------- */ |
1083 |
|
|
1084 |
|
/** |
1085 |
< |
* Applies a supplemental hash function to a given hashCode, which |
1086 |
< |
* defends against poor quality hash functions. The result must |
1087 |
< |
* be non-negative, and for reasonable performance must have good |
1088 |
< |
* avalanche properties; i.e., that each bit of the argument |
1089 |
< |
* affects each bit (except sign bit) of the result. |
1085 |
> |
* Spreads higher bits to lower, and also forces top 2 bits to 0. |
1086 |
> |
* Because the table uses power-of-two masking, sets of hashes |
1087 |
> |
* that vary only in bits above the current mask will always |
1088 |
> |
* collide. (Among known examples are sets of Float keys holding |
1089 |
> |
* consecutive whole numbers in small tables.) To counter this, |
1090 |
> |
* we apply a transform that spreads the impact of higher bits |
1091 |
> |
* downward. There is a tradeoff between speed, utility, and |
1092 |
> |
* quality of bit-spreading. Because many common sets of hashes |
1093 |
> |
* are already reasonably distributed across bits (so don't benefit |
1094 |
> |
* from spreading), and because we use trees to handle large sets |
1095 |
> |
* of collisions in bins, we don't need excessively high quality. |
1096 |
|
*/ |
1097 |
|
private static final int spread(int h) { |
1098 |
< |
// Apply base step of MurmurHash; see http://code.google.com/p/smhasher/ |
1099 |
< |
h ^= h >>> 16; |
1100 |
< |
h *= 0x85ebca6b; |
1101 |
< |
h ^= h >>> 13; |
1102 |
< |
h *= 0xc2b2ae35; |
1103 |
< |
return (h >>> 16) ^ (h & 0x7fffffff); // mask out sign bit |
1098 |
> |
h ^= (h >>> 18) ^ (h >>> 12); |
1099 |
> |
return (h ^ (h >>> 10)) & HASH_BITS; |
1100 |
> |
} |
1101 |
> |
|
1102 |
> |
/** |
1103 |
> |
* Replaces a list bin with a tree bin. Call only when locked. |
1104 |
> |
* Fails to replace if the given key is non-comparable or table |
1105 |
> |
* is, or needs, resizing. |
1106 |
> |
*/ |
1107 |
> |
private final void replaceWithTreeBin(Node[] tab, int index, Object key) { |
1108 |
> |
if ((key instanceof Comparable) && |
1109 |
> |
(tab.length >= MAXIMUM_CAPACITY || counter.sum() < (long)sizeCtl)) { |
1110 |
> |
TreeBin t = new TreeBin(); |
1111 |
> |
for (Node e = tabAt(tab, index); e != null; e = e.next) |
1112 |
> |
t.putTreeNode(e.hash & HASH_BITS, e.key, e.val); |
1113 |
> |
setTabAt(tab, index, new Node(MOVED, t, null, null)); |
1114 |
> |
} |
1115 |
|
} |
1116 |
|
|
1117 |
+ |
/* ---------------- Internal access and update methods -------------- */ |
1118 |
+ |
|
1119 |
|
/** Implementation for get and containsKey */ |
1120 |
|
private final Object internalGet(Object k) { |
1121 |
|
int h = spread(k.hashCode()); |
1122 |
|
retry: for (Node[] tab = table; tab != null;) { |
1123 |
< |
Node e; Object ek, ev; int eh; // locals to read fields once |
1123 |
> |
Node e, p; Object ek, ev; int eh; // locals to read fields once |
1124 |
|
for (e = tabAt(tab, (tab.length - 1) & h); e != null; e = e.next) { |
1125 |
< |
if ((eh = e.hash) == h) { |
1126 |
< |
if ((ev = e.val) != null && |
1127 |
< |
((ek = e.key) == k || k.equals(ek))) |
1128 |
< |
return ev; |
1129 |
< |
} |
1130 |
< |
else if (eh < 0) { // sign bit set |
1131 |
< |
tab = (Node[])e.key; // bin was moved during resize |
494 |
< |
continue retry; |
1125 |
> |
if ((eh = e.hash) == MOVED) { |
1126 |
> |
if ((ek = e.key) instanceof TreeBin) // search TreeBin |
1127 |
> |
return ((TreeBin)ek).getValue(h, k); |
1128 |
> |
else { // restart with new table |
1129 |
> |
tab = (Node[])ek; |
1130 |
> |
continue retry; |
1131 |
> |
} |
1132 |
|
} |
1133 |
+ |
else if ((eh & HASH_BITS) == h && (ev = e.val) != null && |
1134 |
+ |
((ek = e.key) == k || k.equals(ek))) |
1135 |
+ |
return ev; |
1136 |
|
} |
1137 |
|
break; |
1138 |
|
} |
1139 |
|
return null; |
1140 |
|
} |
1141 |
|
|
1142 |
< |
/** Implementation for put and putIfAbsent */ |
1143 |
< |
private final Object internalPut(Object k, Object v, boolean replace) { |
1142 |
> |
/** |
1143 |
> |
* Implementation for the four public remove/replace methods: |
1144 |
> |
* Replaces node value with v, conditional upon match of cv if |
1145 |
> |
* non-null. If resulting value is null, delete. |
1146 |
> |
*/ |
1147 |
> |
private final Object internalReplace(Object k, Object v, Object cv) { |
1148 |
> |
int h = spread(k.hashCode()); |
1149 |
> |
Object oldVal = null; |
1150 |
> |
for (Node[] tab = table;;) { |
1151 |
> |
Node f; int i, fh; Object fk; |
1152 |
> |
if (tab == null || |
1153 |
> |
(f = tabAt(tab, i = (tab.length - 1) & h)) == null) |
1154 |
> |
break; |
1155 |
> |
else if ((fh = f.hash) == MOVED) { |
1156 |
> |
if ((fk = f.key) instanceof TreeBin) { |
1157 |
> |
TreeBin t = (TreeBin)fk; |
1158 |
> |
boolean validated = false; |
1159 |
> |
boolean deleted = false; |
1160 |
> |
t.acquire(0); |
1161 |
> |
try { |
1162 |
> |
if (tabAt(tab, i) == f) { |
1163 |
> |
validated = true; |
1164 |
> |
TreeNode p = t.getTreeNode(h, k, t.root); |
1165 |
> |
if (p != null) { |
1166 |
> |
Object pv = p.val; |
1167 |
> |
if (cv == null || cv == pv || cv.equals(pv)) { |
1168 |
> |
oldVal = pv; |
1169 |
> |
if ((p.val = v) == null) { |
1170 |
> |
deleted = true; |
1171 |
> |
t.deleteTreeNode(p); |
1172 |
> |
} |
1173 |
> |
} |
1174 |
> |
} |
1175 |
> |
} |
1176 |
> |
} finally { |
1177 |
> |
t.release(0); |
1178 |
> |
} |
1179 |
> |
if (validated) { |
1180 |
> |
if (deleted) |
1181 |
> |
counter.add(-1L); |
1182 |
> |
break; |
1183 |
> |
} |
1184 |
> |
} |
1185 |
> |
else |
1186 |
> |
tab = (Node[])fk; |
1187 |
> |
} |
1188 |
> |
else if ((fh & HASH_BITS) != h && f.next == null) // precheck |
1189 |
> |
break; // rules out possible existence |
1190 |
> |
else if ((fh & LOCKED) != 0) { |
1191 |
> |
checkForResize(); // try resizing if can't get lock |
1192 |
> |
f.tryAwaitLock(tab, i); |
1193 |
> |
} |
1194 |
> |
else if (f.casHash(fh, fh | LOCKED)) { |
1195 |
> |
boolean validated = false; |
1196 |
> |
boolean deleted = false; |
1197 |
> |
try { |
1198 |
> |
if (tabAt(tab, i) == f) { |
1199 |
> |
validated = true; |
1200 |
> |
for (Node e = f, pred = null;;) { |
1201 |
> |
Object ek, ev; |
1202 |
> |
if ((e.hash & HASH_BITS) == h && |
1203 |
> |
((ev = e.val) != null) && |
1204 |
> |
((ek = e.key) == k || k.equals(ek))) { |
1205 |
> |
if (cv == null || cv == ev || cv.equals(ev)) { |
1206 |
> |
oldVal = ev; |
1207 |
> |
if ((e.val = v) == null) { |
1208 |
> |
deleted = true; |
1209 |
> |
Node en = e.next; |
1210 |
> |
if (pred != null) |
1211 |
> |
pred.next = en; |
1212 |
> |
else |
1213 |
> |
setTabAt(tab, i, en); |
1214 |
> |
} |
1215 |
> |
} |
1216 |
> |
break; |
1217 |
> |
} |
1218 |
> |
pred = e; |
1219 |
> |
if ((e = e.next) == null) |
1220 |
> |
break; |
1221 |
> |
} |
1222 |
> |
} |
1223 |
> |
} finally { |
1224 |
> |
if (!f.casHash(fh | LOCKED, fh)) { |
1225 |
> |
f.hash = fh; |
1226 |
> |
synchronized (f) { f.notifyAll(); }; |
1227 |
> |
} |
1228 |
> |
} |
1229 |
> |
if (validated) { |
1230 |
> |
if (deleted) |
1231 |
> |
counter.add(-1L); |
1232 |
> |
break; |
1233 |
> |
} |
1234 |
> |
} |
1235 |
> |
} |
1236 |
> |
return oldVal; |
1237 |
> |
} |
1238 |
> |
|
1239 |
> |
/* |
1240 |
> |
* Internal versions of the five insertion methods, each a |
1241 |
> |
* little more complicated than the last. All have |
1242 |
> |
* the same basic structure as the first (internalPut): |
1243 |
> |
* 1. If table uninitialized, create |
1244 |
> |
* 2. If bin empty, try to CAS new node |
1245 |
> |
* 3. If bin stale, use new table |
1246 |
> |
* 4. if bin converted to TreeBin, validate and relay to TreeBin methods |
1247 |
> |
* 5. Lock and validate; if valid, scan and add or update |
1248 |
> |
* |
1249 |
> |
* The others interweave other checks and/or alternative actions: |
1250 |
> |
* * Plain put checks for and performs resize after insertion. |
1251 |
> |
* * putIfAbsent prescans for mapping without lock (and fails to add |
1252 |
> |
* if present), which also makes pre-emptive resize checks worthwhile. |
1253 |
> |
* * computeIfAbsent extends form used in putIfAbsent with additional |
1254 |
> |
* mechanics to deal with, calls, potential exceptions and null |
1255 |
> |
* returns from function call. |
1256 |
> |
* * compute uses the same function-call mechanics, but without |
1257 |
> |
* the prescans |
1258 |
> |
* * putAll attempts to pre-allocate enough table space |
1259 |
> |
* and more lazily performs count updates and checks. |
1260 |
> |
* |
1261 |
> |
* Someday when details settle down a bit more, it might be worth |
1262 |
> |
* some factoring to reduce sprawl. |
1263 |
> |
*/ |
1264 |
> |
|
1265 |
> |
/** Implementation for put */ |
1266 |
> |
private final Object internalPut(Object k, Object v) { |
1267 |
|
int h = spread(k.hashCode()); |
1268 |
< |
Object oldVal = null; // previous value or null if none |
1268 |
> |
int count = 0; |
1269 |
|
for (Node[] tab = table;;) { |
1270 |
< |
Node e; int i; Object ek, ev; |
1270 |
> |
int i; Node f; int fh; Object fk; |
1271 |
|
if (tab == null) |
1272 |
< |
tab = growTable(); |
1273 |
< |
else if ((e = tabAt(tab, i = (tab.length - 1) & h)) == null) { |
1272 |
> |
tab = initTable(); |
1273 |
> |
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) { |
1274 |
|
if (casTabAt(tab, i, null, new Node(h, k, v, null))) |
1275 |
|
break; // no lock when adding to empty bin |
1276 |
|
} |
1277 |
< |
else if (e.hash < 0) // resized -- restart with new table |
1278 |
< |
tab = (Node[])e.key; |
1279 |
< |
else if (!replace && e.hash == h && (ev = e.val) != null && |
1280 |
< |
((ek = e.key) == k || k.equals(ek))) { |
1281 |
< |
if (tabAt(tab, i) == e) { // inspect and validate 1st node |
1282 |
< |
oldVal = ev; // without lock for putIfAbsent |
1283 |
< |
break; |
1277 |
> |
else if ((fh = f.hash) == MOVED) { |
1278 |
> |
if ((fk = f.key) instanceof TreeBin) { |
1279 |
> |
TreeBin t = (TreeBin)fk; |
1280 |
> |
Object oldVal = null; |
1281 |
> |
t.acquire(0); |
1282 |
> |
try { |
1283 |
> |
if (tabAt(tab, i) == f) { |
1284 |
> |
count = 2; |
1285 |
> |
TreeNode p = t.putTreeNode(h, k, v); |
1286 |
> |
if (p != null) { |
1287 |
> |
oldVal = p.val; |
1288 |
> |
p.val = v; |
1289 |
> |
} |
1290 |
> |
} |
1291 |
> |
} finally { |
1292 |
> |
t.release(0); |
1293 |
> |
} |
1294 |
> |
if (count != 0) { |
1295 |
> |
if (oldVal != null) |
1296 |
> |
return oldVal; |
1297 |
> |
break; |
1298 |
> |
} |
1299 |
|
} |
1300 |
+ |
else |
1301 |
+ |
tab = (Node[])fk; |
1302 |
|
} |
1303 |
< |
else { |
1304 |
< |
boolean validated = false; |
1305 |
< |
boolean checkSize = false; |
1306 |
< |
synchronized (e) { // lock the 1st node of bin list |
1307 |
< |
if (tabAt(tab, i) == e) { |
1308 |
< |
validated = true; // retry if 1st already deleted |
1309 |
< |
for (Node first = e;;) { |
1310 |
< |
if (e.hash == h && |
1311 |
< |
((ek = e.key) == k || k.equals(ek)) && |
1312 |
< |
(ev = e.val) != null) { |
1303 |
> |
else if ((fh & LOCKED) != 0) { |
1304 |
> |
checkForResize(); |
1305 |
> |
f.tryAwaitLock(tab, i); |
1306 |
> |
} |
1307 |
> |
else if (f.casHash(fh, fh | LOCKED)) { |
1308 |
> |
Object oldVal = null; |
1309 |
> |
try { // needed in case equals() throws |
1310 |
> |
if (tabAt(tab, i) == f) { |
1311 |
> |
count = 1; |
1312 |
> |
for (Node e = f;; ++count) { |
1313 |
> |
Object ek, ev; |
1314 |
> |
if ((e.hash & HASH_BITS) == h && |
1315 |
> |
(ev = e.val) != null && |
1316 |
> |
((ek = e.key) == k || k.equals(ek))) { |
1317 |
|
oldVal = ev; |
1318 |
< |
if (replace) |
535 |
< |
e.val = v; |
1318 |
> |
e.val = v; |
1319 |
|
break; |
1320 |
|
} |
1321 |
|
Node last = e; |
1322 |
|
if ((e = e.next) == null) { |
1323 |
|
last.next = new Node(h, k, v, null); |
1324 |
< |
if (last != first || tab.length <= 64) |
1325 |
< |
checkSize = true; |
1324 |
> |
if (count >= TREE_THRESHOLD) |
1325 |
> |
replaceWithTreeBin(tab, i, k); |
1326 |
|
break; |
1327 |
|
} |
1328 |
|
} |
1329 |
|
} |
1330 |
+ |
} finally { // unlock and signal if needed |
1331 |
+ |
if (!f.casHash(fh | LOCKED, fh)) { |
1332 |
+ |
f.hash = fh; |
1333 |
+ |
synchronized (f) { f.notifyAll(); }; |
1334 |
+ |
} |
1335 |
|
} |
1336 |
< |
if (validated) { |
1337 |
< |
if (checkSize && tab.length < MAXIMUM_CAPACITY && |
1338 |
< |
resizing == 0 && counter.sum() >= threshold) |
1339 |
< |
growTable(); |
1336 |
> |
if (count != 0) { |
1337 |
> |
if (oldVal != null) |
1338 |
> |
return oldVal; |
1339 |
> |
if (tab.length <= 64) |
1340 |
> |
count = 2; |
1341 |
|
break; |
1342 |
|
} |
1343 |
|
} |
1344 |
|
} |
1345 |
< |
if (oldVal == null) |
1346 |
< |
counter.increment(); // update counter outside of locks |
1347 |
< |
return oldVal; |
1345 |
> |
counter.add(1L); |
1346 |
> |
if (count > 1) |
1347 |
> |
checkForResize(); |
1348 |
> |
return null; |
1349 |
|
} |
1350 |
|
|
1351 |
< |
/** |
1352 |
< |
* Implementation for the four public remove/replace methods: |
563 |
< |
* Replaces node value with v, conditional upon match of cv if |
564 |
< |
* non-null. If resulting value is null, delete. |
565 |
< |
*/ |
566 |
< |
private final Object internalReplace(Object k, Object v, Object cv) { |
1351 |
> |
/** Implementation for putIfAbsent */ |
1352 |
> |
private final Object internalPutIfAbsent(Object k, Object v) { |
1353 |
|
int h = spread(k.hashCode()); |
1354 |
+ |
int count = 0; |
1355 |
|
for (Node[] tab = table;;) { |
1356 |
< |
Node e; int i; |
1357 |
< |
if (tab == null || |
1358 |
< |
(e = tabAt(tab, i = (tab.length - 1) & h)) == null) |
1359 |
< |
return null; |
1360 |
< |
else if (e.hash < 0) |
1361 |
< |
tab = (Node[])e.key; |
1356 |
> |
int i; Node f; int fh; Object fk, fv; |
1357 |
> |
if (tab == null) |
1358 |
> |
tab = initTable(); |
1359 |
> |
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) { |
1360 |
> |
if (casTabAt(tab, i, null, new Node(h, k, v, null))) |
1361 |
> |
break; |
1362 |
> |
} |
1363 |
> |
else if ((fh = f.hash) == MOVED) { |
1364 |
> |
if ((fk = f.key) instanceof TreeBin) { |
1365 |
> |
TreeBin t = (TreeBin)fk; |
1366 |
> |
Object oldVal = null; |
1367 |
> |
t.acquire(0); |
1368 |
> |
try { |
1369 |
> |
if (tabAt(tab, i) == f) { |
1370 |
> |
count = 2; |
1371 |
> |
TreeNode p = t.putTreeNode(h, k, v); |
1372 |
> |
if (p != null) |
1373 |
> |
oldVal = p.val; |
1374 |
> |
} |
1375 |
> |
} finally { |
1376 |
> |
t.release(0); |
1377 |
> |
} |
1378 |
> |
if (count != 0) { |
1379 |
> |
if (oldVal != null) |
1380 |
> |
return oldVal; |
1381 |
> |
break; |
1382 |
> |
} |
1383 |
> |
} |
1384 |
> |
else |
1385 |
> |
tab = (Node[])fk; |
1386 |
> |
} |
1387 |
> |
else if ((fh & HASH_BITS) == h && (fv = f.val) != null && |
1388 |
> |
((fk = f.key) == k || k.equals(fk))) |
1389 |
> |
return fv; |
1390 |
|
else { |
1391 |
< |
Object oldVal = null; |
1392 |
< |
boolean validated = false; |
1393 |
< |
boolean deleted = false; |
1394 |
< |
synchronized (e) { |
1395 |
< |
if (tabAt(tab, i) == e) { |
1396 |
< |
validated = true; |
1397 |
< |
Node pred = null; |
1398 |
< |
do { |
1399 |
< |
Object ek, ev; |
1400 |
< |
if (e.hash == h && |
1401 |
< |
((ek = e.key) == k || k.equals(ek)) && |
1402 |
< |
((ev = e.val) != null)) { |
1403 |
< |
if (cv == null || cv == ev || cv.equals(ev)) { |
1391 |
> |
Node g = f.next; |
1392 |
> |
if (g != null) { // at least 2 nodes -- search and maybe resize |
1393 |
> |
for (Node e = g;;) { |
1394 |
> |
Object ek, ev; |
1395 |
> |
if ((e.hash & HASH_BITS) == h && (ev = e.val) != null && |
1396 |
> |
((ek = e.key) == k || k.equals(ek))) |
1397 |
> |
return ev; |
1398 |
> |
if ((e = e.next) == null) { |
1399 |
> |
checkForResize(); |
1400 |
> |
break; |
1401 |
> |
} |
1402 |
> |
} |
1403 |
> |
} |
1404 |
> |
if (((fh = f.hash) & LOCKED) != 0) { |
1405 |
> |
checkForResize(); |
1406 |
> |
f.tryAwaitLock(tab, i); |
1407 |
> |
} |
1408 |
> |
else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) { |
1409 |
> |
Object oldVal = null; |
1410 |
> |
try { |
1411 |
> |
if (tabAt(tab, i) == f) { |
1412 |
> |
count = 1; |
1413 |
> |
for (Node e = f;; ++count) { |
1414 |
> |
Object ek, ev; |
1415 |
> |
if ((e.hash & HASH_BITS) == h && |
1416 |
> |
(ev = e.val) != null && |
1417 |
> |
((ek = e.key) == k || k.equals(ek))) { |
1418 |
|
oldVal = ev; |
1419 |
< |
if ((e.val = v) == null) { |
1420 |
< |
deleted = true; |
1421 |
< |
Node en = e.next; |
1422 |
< |
if (pred != null) |
1423 |
< |
pred.next = en; |
1424 |
< |
else |
1425 |
< |
setTabAt(tab, i, en); |
1426 |
< |
} |
1419 |
> |
break; |
1420 |
> |
} |
1421 |
> |
Node last = e; |
1422 |
> |
if ((e = e.next) == null) { |
1423 |
> |
last.next = new Node(h, k, v, null); |
1424 |
> |
if (count >= TREE_THRESHOLD) |
1425 |
> |
replaceWithTreeBin(tab, i, k); |
1426 |
> |
break; |
1427 |
|
} |
599 |
– |
break; |
1428 |
|
} |
1429 |
< |
} while ((e = (pred = e).next) != null); |
1429 |
> |
} |
1430 |
> |
} finally { |
1431 |
> |
if (!f.casHash(fh | LOCKED, fh)) { |
1432 |
> |
f.hash = fh; |
1433 |
> |
synchronized (f) { f.notifyAll(); }; |
1434 |
> |
} |
1435 |
> |
} |
1436 |
> |
if (count != 0) { |
1437 |
> |
if (oldVal != null) |
1438 |
> |
return oldVal; |
1439 |
> |
if (tab.length <= 64) |
1440 |
> |
count = 2; |
1441 |
> |
break; |
1442 |
|
} |
603 |
– |
} |
604 |
– |
if (validated) { |
605 |
– |
if (deleted) |
606 |
– |
counter.decrement(); |
607 |
– |
return oldVal; |
1443 |
|
} |
1444 |
|
} |
1445 |
|
} |
1446 |
+ |
counter.add(1L); |
1447 |
+ |
if (count > 1) |
1448 |
+ |
checkForResize(); |
1449 |
+ |
return null; |
1450 |
|
} |
1451 |
|
|
1452 |
< |
/** Implementation for computeIfAbsent and compute. Like put, but messier. */ |
1453 |
< |
@SuppressWarnings("unchecked") |
1454 |
< |
private final V internalCompute(K k, |
616 |
< |
MappingFunction<? super K, ? extends V> f, |
617 |
< |
boolean replace) { |
1452 |
> |
/** Implementation for computeIfAbsent */ |
1453 |
> |
private final Object internalComputeIfAbsent(K k, |
1454 |
> |
MappingFunction<? super K, ?> mf) { |
1455 |
|
int h = spread(k.hashCode()); |
1456 |
< |
V val = null; |
1457 |
< |
boolean added = false; |
1458 |
< |
Node[] tab = table; |
1459 |
< |
outer:for (;;) { |
623 |
< |
Node e; int i; Object ek, ev; |
1456 |
> |
Object val = null; |
1457 |
> |
int count = 0; |
1458 |
> |
for (Node[] tab = table;;) { |
1459 |
> |
Node f; int i, fh; Object fk, fv; |
1460 |
|
if (tab == null) |
1461 |
< |
tab = growTable(); |
1462 |
< |
else if ((e = tabAt(tab, i = (tab.length - 1) & h)) == null) { |
1463 |
< |
Node node = new Node(h, k, null, null); |
1464 |
< |
boolean validated = false; |
1465 |
< |
synchronized (node) { // must lock while computing value |
1466 |
< |
if (casTabAt(tab, i, null, node)) { |
1467 |
< |
validated = true; |
1468 |
< |
try { |
1469 |
< |
val = f.map(k); |
1470 |
< |
if (val != null) { |
1471 |
< |
node.val = val; |
1461 |
> |
tab = initTable(); |
1462 |
> |
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) { |
1463 |
> |
Node node = new Node(fh = h | LOCKED, k, null, null); |
1464 |
> |
if (casTabAt(tab, i, null, node)) { |
1465 |
> |
count = 1; |
1466 |
> |
try { |
1467 |
> |
if ((val = mf.map(k)) != null) |
1468 |
> |
node.val = val; |
1469 |
> |
} finally { |
1470 |
> |
if (val == null) |
1471 |
> |
setTabAt(tab, i, null); |
1472 |
> |
if (!node.casHash(fh, h)) { |
1473 |
> |
node.hash = h; |
1474 |
> |
synchronized (node) { node.notifyAll(); }; |
1475 |
> |
} |
1476 |
> |
} |
1477 |
> |
} |
1478 |
> |
if (count != 0) |
1479 |
> |
break; |
1480 |
> |
} |
1481 |
> |
else if ((fh = f.hash) == MOVED) { |
1482 |
> |
if ((fk = f.key) instanceof TreeBin) { |
1483 |
> |
TreeBin t = (TreeBin)fk; |
1484 |
> |
boolean added = false; |
1485 |
> |
t.acquire(0); |
1486 |
> |
try { |
1487 |
> |
if (tabAt(tab, i) == f) { |
1488 |
> |
count = 1; |
1489 |
> |
TreeNode p = t.getTreeNode(h, k, t.root); |
1490 |
> |
if (p != null) |
1491 |
> |
val = p.val; |
1492 |
> |
else if ((val = mf.map(k)) != null) { |
1493 |
|
added = true; |
1494 |
+ |
count = 2; |
1495 |
+ |
t.putTreeNode(h, k, val); |
1496 |
|
} |
638 |
– |
} finally { |
639 |
– |
if (!added) |
640 |
– |
setTabAt(tab, i, null); |
1497 |
|
} |
1498 |
+ |
} finally { |
1499 |
+ |
t.release(0); |
1500 |
+ |
} |
1501 |
+ |
if (count != 0) { |
1502 |
+ |
if (!added) |
1503 |
+ |
return val; |
1504 |
+ |
break; |
1505 |
+ |
} |
1506 |
+ |
} |
1507 |
+ |
else |
1508 |
+ |
tab = (Node[])fk; |
1509 |
+ |
} |
1510 |
+ |
else if ((fh & HASH_BITS) == h && (fv = f.val) != null && |
1511 |
+ |
((fk = f.key) == k || k.equals(fk))) |
1512 |
+ |
return fv; |
1513 |
+ |
else { |
1514 |
+ |
Node g = f.next; |
1515 |
+ |
if (g != null) { |
1516 |
+ |
for (Node e = g;;) { |
1517 |
+ |
Object ek, ev; |
1518 |
+ |
if ((e.hash & HASH_BITS) == h && (ev = e.val) != null && |
1519 |
+ |
((ek = e.key) == k || k.equals(ek))) |
1520 |
+ |
return ev; |
1521 |
+ |
if ((e = e.next) == null) { |
1522 |
+ |
checkForResize(); |
1523 |
+ |
break; |
1524 |
+ |
} |
1525 |
+ |
} |
1526 |
+ |
} |
1527 |
+ |
if (((fh = f.hash) & LOCKED) != 0) { |
1528 |
+ |
checkForResize(); |
1529 |
+ |
f.tryAwaitLock(tab, i); |
1530 |
+ |
} |
1531 |
+ |
else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) { |
1532 |
+ |
boolean added = false; |
1533 |
+ |
try { |
1534 |
+ |
if (tabAt(tab, i) == f) { |
1535 |
+ |
count = 1; |
1536 |
+ |
for (Node e = f;; ++count) { |
1537 |
+ |
Object ek, ev; |
1538 |
+ |
if ((e.hash & HASH_BITS) == h && |
1539 |
+ |
(ev = e.val) != null && |
1540 |
+ |
((ek = e.key) == k || k.equals(ek))) { |
1541 |
+ |
val = ev; |
1542 |
+ |
break; |
1543 |
+ |
} |
1544 |
+ |
Node last = e; |
1545 |
+ |
if ((e = e.next) == null) { |
1546 |
+ |
if ((val = mf.map(k)) != null) { |
1547 |
+ |
added = true; |
1548 |
+ |
last.next = new Node(h, k, val, null); |
1549 |
+ |
if (count >= TREE_THRESHOLD) |
1550 |
+ |
replaceWithTreeBin(tab, i, k); |
1551 |
+ |
} |
1552 |
+ |
break; |
1553 |
+ |
} |
1554 |
+ |
} |
1555 |
+ |
} |
1556 |
+ |
} finally { |
1557 |
+ |
if (!f.casHash(fh | LOCKED, fh)) { |
1558 |
+ |
f.hash = fh; |
1559 |
+ |
synchronized (f) { f.notifyAll(); }; |
1560 |
+ |
} |
1561 |
+ |
} |
1562 |
+ |
if (count != 0) { |
1563 |
+ |
if (!added) |
1564 |
+ |
return val; |
1565 |
+ |
if (tab.length <= 64) |
1566 |
+ |
count = 2; |
1567 |
+ |
break; |
1568 |
|
} |
1569 |
|
} |
644 |
– |
if (validated) |
645 |
– |
break; |
1570 |
|
} |
1571 |
< |
else if (e.hash < 0) |
1572 |
< |
tab = (Node[])e.key; |
1573 |
< |
else if (!replace && e.hash == h && (ev = e.val) != null && |
1574 |
< |
((ek = e.key) == k || k.equals(ek))) { |
1575 |
< |
if (tabAt(tab, i) == e) { |
1576 |
< |
val = (V)ev; |
1571 |
> |
} |
1572 |
> |
if (val != null) { |
1573 |
> |
counter.add(1L); |
1574 |
> |
if (count > 1) |
1575 |
> |
checkForResize(); |
1576 |
> |
} |
1577 |
> |
return val; |
1578 |
> |
} |
1579 |
> |
|
1580 |
> |
/** Implementation for compute */ |
1581 |
> |
@SuppressWarnings("unchecked") |
1582 |
> |
private final Object internalCompute(K k, |
1583 |
> |
RemappingFunction<? super K, V> mf) { |
1584 |
> |
int h = spread(k.hashCode()); |
1585 |
> |
Object val = null; |
1586 |
> |
int delta = 0; |
1587 |
> |
int count = 0; |
1588 |
> |
for (Node[] tab = table;;) { |
1589 |
> |
Node f; int i, fh; Object fk; |
1590 |
> |
if (tab == null) |
1591 |
> |
tab = initTable(); |
1592 |
> |
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) { |
1593 |
> |
Node node = new Node(fh = h | LOCKED, k, null, null); |
1594 |
> |
if (casTabAt(tab, i, null, node)) { |
1595 |
> |
try { |
1596 |
> |
count = 1; |
1597 |
> |
if ((val = mf.remap(k, null)) != null) { |
1598 |
> |
node.val = val; |
1599 |
> |
delta = 1; |
1600 |
> |
} |
1601 |
> |
} finally { |
1602 |
> |
if (delta == 0) |
1603 |
> |
setTabAt(tab, i, null); |
1604 |
> |
if (!node.casHash(fh, h)) { |
1605 |
> |
node.hash = h; |
1606 |
> |
synchronized (node) { node.notifyAll(); }; |
1607 |
> |
} |
1608 |
> |
} |
1609 |
> |
} |
1610 |
> |
if (count != 0) |
1611 |
|
break; |
1612 |
+ |
} |
1613 |
+ |
else if ((fh = f.hash) == MOVED) { |
1614 |
+ |
if ((fk = f.key) instanceof TreeBin) { |
1615 |
+ |
TreeBin t = (TreeBin)fk; |
1616 |
+ |
t.acquire(0); |
1617 |
+ |
try { |
1618 |
+ |
if (tabAt(tab, i) == f) { |
1619 |
+ |
count = 1; |
1620 |
+ |
TreeNode p = t.getTreeNode(h, k, t.root); |
1621 |
+ |
Object pv = (p == null) ? null : p.val; |
1622 |
+ |
if ((val = mf.remap(k, (V)pv)) != null) { |
1623 |
+ |
if (p != null) |
1624 |
+ |
p.val = val; |
1625 |
+ |
else { |
1626 |
+ |
count = 2; |
1627 |
+ |
delta = 1; |
1628 |
+ |
t.putTreeNode(h, k, val); |
1629 |
+ |
} |
1630 |
+ |
} |
1631 |
+ |
else if (p != null) { |
1632 |
+ |
delta = -1; |
1633 |
+ |
t.deleteTreeNode(p); |
1634 |
+ |
} |
1635 |
+ |
} |
1636 |
+ |
} finally { |
1637 |
+ |
t.release(0); |
1638 |
+ |
} |
1639 |
+ |
if (count != 0) |
1640 |
+ |
break; |
1641 |
|
} |
1642 |
+ |
else |
1643 |
+ |
tab = (Node[])fk; |
1644 |
|
} |
1645 |
< |
else if (Thread.holdsLock(e)) |
1646 |
< |
throw new IllegalStateException("Recursive map computation"); |
1647 |
< |
else { |
1648 |
< |
boolean validated = false; |
1649 |
< |
boolean checkSize = false; |
1650 |
< |
synchronized (e) { |
1651 |
< |
if (tabAt(tab, i) == e) { |
1652 |
< |
validated = true; |
1653 |
< |
for (Node first = e;;) { |
1654 |
< |
if (e.hash == h && |
1655 |
< |
((ek = e.key) == k || k.equals(ek)) && |
1656 |
< |
((ev = e.val) != null)) { |
1657 |
< |
Object fv; |
1658 |
< |
if (replace && (fv = f.map(k)) != null) |
1659 |
< |
ev = e.val = fv; |
1660 |
< |
val = (V)ev; |
1645 |
> |
else if ((fh & LOCKED) != 0) { |
1646 |
> |
checkForResize(); |
1647 |
> |
f.tryAwaitLock(tab, i); |
1648 |
> |
} |
1649 |
> |
else if (f.casHash(fh, fh | LOCKED)) { |
1650 |
> |
try { |
1651 |
> |
if (tabAt(tab, i) == f) { |
1652 |
> |
count = 1; |
1653 |
> |
for (Node e = f, pred = null;; ++count) { |
1654 |
> |
Object ek, ev; |
1655 |
> |
if ((e.hash & HASH_BITS) == h && |
1656 |
> |
(ev = e.val) != null && |
1657 |
> |
((ek = e.key) == k || k.equals(ek))) { |
1658 |
> |
val = mf.remap(k, (V)ev); |
1659 |
> |
if (val != null) |
1660 |
> |
e.val = val; |
1661 |
> |
else { |
1662 |
> |
delta = -1; |
1663 |
> |
Node en = e.next; |
1664 |
> |
if (pred != null) |
1665 |
> |
pred.next = en; |
1666 |
> |
else |
1667 |
> |
setTabAt(tab, i, en); |
1668 |
> |
} |
1669 |
|
break; |
1670 |
|
} |
1671 |
< |
Node last = e; |
1671 |
> |
pred = e; |
1672 |
|
if ((e = e.next) == null) { |
1673 |
< |
if ((val = f.map(k)) != null) { |
1674 |
< |
last.next = new Node(h, k, val, null); |
1675 |
< |
added = true; |
1676 |
< |
if (last != first || tab.length <= 64) |
1677 |
< |
checkSize = true; |
1673 |
> |
if ((val = mf.remap(k, null)) != null) { |
1674 |
> |
pred.next = new Node(h, k, val, null); |
1675 |
> |
delta = 1; |
1676 |
> |
if (count >= TREE_THRESHOLD) |
1677 |
> |
replaceWithTreeBin(tab, i, k); |
1678 |
|
} |
1679 |
|
break; |
1680 |
|
} |
1681 |
|
} |
1682 |
|
} |
1683 |
+ |
} finally { |
1684 |
+ |
if (!f.casHash(fh | LOCKED, fh)) { |
1685 |
+ |
f.hash = fh; |
1686 |
+ |
synchronized (f) { f.notifyAll(); }; |
1687 |
+ |
} |
1688 |
|
} |
1689 |
< |
if (validated) { |
1690 |
< |
if (checkSize && tab.length < MAXIMUM_CAPACITY && |
1691 |
< |
resizing == 0 && counter.sum() >= threshold) |
690 |
< |
growTable(); |
1689 |
> |
if (count != 0) { |
1690 |
> |
if (tab.length <= 64) |
1691 |
> |
count = 2; |
1692 |
|
break; |
1693 |
|
} |
1694 |
|
} |
1695 |
|
} |
1696 |
< |
if (added) |
1697 |
< |
counter.increment(); |
1696 |
> |
if (delta != 0) { |
1697 |
> |
counter.add((long)delta); |
1698 |
> |
if (count > 1) |
1699 |
> |
checkForResize(); |
1700 |
> |
} |
1701 |
|
return val; |
1702 |
|
} |
1703 |
|
|
1704 |
+ |
/** Implementation for putAll */ |
1705 |
+ |
private final void internalPutAll(Map<?, ?> m) { |
1706 |
+ |
tryPresize(m.size()); |
1707 |
+ |
long delta = 0L; // number of uncommitted additions |
1708 |
+ |
boolean npe = false; // to throw exception on exit for nulls |
1709 |
+ |
try { // to clean up counts on other exceptions |
1710 |
+ |
for (Map.Entry<?, ?> entry : m.entrySet()) { |
1711 |
+ |
Object k, v; |
1712 |
+ |
if (entry == null || (k = entry.getKey()) == null || |
1713 |
+ |
(v = entry.getValue()) == null) { |
1714 |
+ |
npe = true; |
1715 |
+ |
break; |
1716 |
+ |
} |
1717 |
+ |
int h = spread(k.hashCode()); |
1718 |
+ |
for (Node[] tab = table;;) { |
1719 |
+ |
int i; Node f; int fh; Object fk; |
1720 |
+ |
if (tab == null) |
1721 |
+ |
tab = initTable(); |
1722 |
+ |
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null){ |
1723 |
+ |
if (casTabAt(tab, i, null, new Node(h, k, v, null))) { |
1724 |
+ |
++delta; |
1725 |
+ |
break; |
1726 |
+ |
} |
1727 |
+ |
} |
1728 |
+ |
else if ((fh = f.hash) == MOVED) { |
1729 |
+ |
if ((fk = f.key) instanceof TreeBin) { |
1730 |
+ |
TreeBin t = (TreeBin)fk; |
1731 |
+ |
boolean validated = false; |
1732 |
+ |
t.acquire(0); |
1733 |
+ |
try { |
1734 |
+ |
if (tabAt(tab, i) == f) { |
1735 |
+ |
validated = true; |
1736 |
+ |
TreeNode p = t.getTreeNode(h, k, t.root); |
1737 |
+ |
if (p != null) |
1738 |
+ |
p.val = v; |
1739 |
+ |
else { |
1740 |
+ |
t.putTreeNode(h, k, v); |
1741 |
+ |
++delta; |
1742 |
+ |
} |
1743 |
+ |
} |
1744 |
+ |
} finally { |
1745 |
+ |
t.release(0); |
1746 |
+ |
} |
1747 |
+ |
if (validated) |
1748 |
+ |
break; |
1749 |
+ |
} |
1750 |
+ |
else |
1751 |
+ |
tab = (Node[])fk; |
1752 |
+ |
} |
1753 |
+ |
else if ((fh & LOCKED) != 0) { |
1754 |
+ |
counter.add(delta); |
1755 |
+ |
delta = 0L; |
1756 |
+ |
checkForResize(); |
1757 |
+ |
f.tryAwaitLock(tab, i); |
1758 |
+ |
} |
1759 |
+ |
else if (f.casHash(fh, fh | LOCKED)) { |
1760 |
+ |
int count = 0; |
1761 |
+ |
try { |
1762 |
+ |
if (tabAt(tab, i) == f) { |
1763 |
+ |
count = 1; |
1764 |
+ |
for (Node e = f;; ++count) { |
1765 |
+ |
Object ek, ev; |
1766 |
+ |
if ((e.hash & HASH_BITS) == h && |
1767 |
+ |
(ev = e.val) != null && |
1768 |
+ |
((ek = e.key) == k || k.equals(ek))) { |
1769 |
+ |
e.val = v; |
1770 |
+ |
break; |
1771 |
+ |
} |
1772 |
+ |
Node last = e; |
1773 |
+ |
if ((e = e.next) == null) { |
1774 |
+ |
++delta; |
1775 |
+ |
last.next = new Node(h, k, v, null); |
1776 |
+ |
if (count >= TREE_THRESHOLD) |
1777 |
+ |
replaceWithTreeBin(tab, i, k); |
1778 |
+ |
break; |
1779 |
+ |
} |
1780 |
+ |
} |
1781 |
+ |
} |
1782 |
+ |
} finally { |
1783 |
+ |
if (!f.casHash(fh | LOCKED, fh)) { |
1784 |
+ |
f.hash = fh; |
1785 |
+ |
synchronized (f) { f.notifyAll(); }; |
1786 |
+ |
} |
1787 |
+ |
} |
1788 |
+ |
if (count != 0) { |
1789 |
+ |
if (count > 1) { |
1790 |
+ |
counter.add(delta); |
1791 |
+ |
delta = 0L; |
1792 |
+ |
checkForResize(); |
1793 |
+ |
} |
1794 |
+ |
break; |
1795 |
+ |
} |
1796 |
+ |
} |
1797 |
+ |
} |
1798 |
+ |
} |
1799 |
+ |
} finally { |
1800 |
+ |
if (delta != 0) |
1801 |
+ |
counter.add(delta); |
1802 |
+ |
} |
1803 |
+ |
if (npe) |
1804 |
+ |
throw new NullPointerException(); |
1805 |
+ |
} |
1806 |
+ |
|
1807 |
+ |
/* ---------------- Table Initialization and Resizing -------------- */ |
1808 |
+ |
|
1809 |
+ |
/** |
1810 |
+ |
* Returns a power of two table size for the given desired capacity. |
1811 |
+ |
* See Hackers Delight, sec 3.2 |
1812 |
+ |
*/ |
1813 |
+ |
private static final int tableSizeFor(int c) { |
1814 |
+ |
int n = c - 1; |
1815 |
+ |
n |= n >>> 1; |
1816 |
+ |
n |= n >>> 2; |
1817 |
+ |
n |= n >>> 4; |
1818 |
+ |
n |= n >>> 8; |
1819 |
+ |
n |= n >>> 16; |
1820 |
+ |
return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1; |
1821 |
+ |
} |
1822 |
+ |
|
1823 |
+ |
/** |
1824 |
+ |
* Initializes table, using the size recorded in sizeCtl. |
1825 |
+ |
*/ |
1826 |
+ |
private final Node[] initTable() { |
1827 |
+ |
Node[] tab; int sc; |
1828 |
+ |
while ((tab = table) == null) { |
1829 |
+ |
if ((sc = sizeCtl) < 0) |
1830 |
+ |
Thread.yield(); // lost initialization race; just spin |
1831 |
+ |
else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) { |
1832 |
+ |
try { |
1833 |
+ |
if ((tab = table) == null) { |
1834 |
+ |
int n = (sc > 0) ? sc : DEFAULT_CAPACITY; |
1835 |
+ |
tab = table = new Node[n]; |
1836 |
+ |
sc = n - (n >>> 2); |
1837 |
+ |
} |
1838 |
+ |
} finally { |
1839 |
+ |
sizeCtl = sc; |
1840 |
+ |
} |
1841 |
+ |
break; |
1842 |
+ |
} |
1843 |
+ |
} |
1844 |
+ |
return tab; |
1845 |
+ |
} |
1846 |
+ |
|
1847 |
+ |
/** |
1848 |
+ |
* If table is too small and not already resizing, creates next |
1849 |
+ |
* table and transfers bins. Rechecks occupancy after a transfer |
1850 |
+ |
* to see if another resize is already needed because resizings |
1851 |
+ |
* are lagging additions. |
1852 |
+ |
*/ |
1853 |
+ |
private final void checkForResize() { |
1854 |
+ |
Node[] tab; int n, sc; |
1855 |
+ |
while ((tab = table) != null && |
1856 |
+ |
(n = tab.length) < MAXIMUM_CAPACITY && |
1857 |
+ |
(sc = sizeCtl) >= 0 && counter.sum() >= (long)sc && |
1858 |
+ |
UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) { |
1859 |
+ |
try { |
1860 |
+ |
if (tab == table) { |
1861 |
+ |
table = rebuild(tab); |
1862 |
+ |
sc = (n << 1) - (n >>> 1); |
1863 |
+ |
} |
1864 |
+ |
} finally { |
1865 |
+ |
sizeCtl = sc; |
1866 |
+ |
} |
1867 |
+ |
} |
1868 |
+ |
} |
1869 |
+ |
|
1870 |
+ |
/** |
1871 |
+ |
* Tries to presize table to accommodate the given number of elements. |
1872 |
+ |
* |
1873 |
+ |
* @param size number of elements (doesn't need to be perfectly accurate) |
1874 |
+ |
*/ |
1875 |
+ |
private final void tryPresize(int size) { |
1876 |
+ |
int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY : |
1877 |
+ |
tableSizeFor(size + (size >>> 1) + 1); |
1878 |
+ |
int sc; |
1879 |
+ |
while ((sc = sizeCtl) >= 0) { |
1880 |
+ |
Node[] tab = table; int n; |
1881 |
+ |
if (tab == null || (n = tab.length) == 0) { |
1882 |
+ |
n = (sc > c) ? sc : c; |
1883 |
+ |
if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) { |
1884 |
+ |
try { |
1885 |
+ |
if (table == tab) { |
1886 |
+ |
table = new Node[n]; |
1887 |
+ |
sc = n - (n >>> 2); |
1888 |
+ |
} |
1889 |
+ |
} finally { |
1890 |
+ |
sizeCtl = sc; |
1891 |
+ |
} |
1892 |
+ |
} |
1893 |
+ |
} |
1894 |
+ |
else if (c <= sc || n >= MAXIMUM_CAPACITY) |
1895 |
+ |
break; |
1896 |
+ |
else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) { |
1897 |
+ |
try { |
1898 |
+ |
if (table == tab) { |
1899 |
+ |
table = rebuild(tab); |
1900 |
+ |
sc = (n << 1) - (n >>> 1); |
1901 |
+ |
} |
1902 |
+ |
} finally { |
1903 |
+ |
sizeCtl = sc; |
1904 |
+ |
} |
1905 |
+ |
} |
1906 |
+ |
} |
1907 |
+ |
} |
1908 |
+ |
|
1909 |
+ |
/* |
1910 |
+ |
* Moves and/or copies the nodes in each bin to new table. See |
1911 |
+ |
* above for explanation. |
1912 |
+ |
* |
1913 |
+ |
* @return the new table |
1914 |
+ |
*/ |
1915 |
+ |
private static final Node[] rebuild(Node[] tab) { |
1916 |
+ |
int n = tab.length; |
1917 |
+ |
Node[] nextTab = new Node[n << 1]; |
1918 |
+ |
Node fwd = new Node(MOVED, nextTab, null, null); |
1919 |
+ |
int[] buffer = null; // holds bins to revisit; null until needed |
1920 |
+ |
Node rev = null; // reverse forwarder; null until needed |
1921 |
+ |
int nbuffered = 0; // the number of bins in buffer list |
1922 |
+ |
int bufferIndex = 0; // buffer index of current buffered bin |
1923 |
+ |
int bin = n - 1; // current non-buffered bin or -1 if none |
1924 |
+ |
|
1925 |
+ |
for (int i = bin;;) { // start upwards sweep |
1926 |
+ |
int fh; Node f; |
1927 |
+ |
if ((f = tabAt(tab, i)) == null) { |
1928 |
+ |
if (bin >= 0) { // no lock needed (or available) |
1929 |
+ |
if (!casTabAt(tab, i, f, fwd)) |
1930 |
+ |
continue; |
1931 |
+ |
} |
1932 |
+ |
else { // transiently use a locked forwarding node |
1933 |
+ |
Node g = new Node(MOVED|LOCKED, nextTab, null, null); |
1934 |
+ |
if (!casTabAt(tab, i, f, g)) |
1935 |
+ |
continue; |
1936 |
+ |
setTabAt(nextTab, i, null); |
1937 |
+ |
setTabAt(nextTab, i + n, null); |
1938 |
+ |
setTabAt(tab, i, fwd); |
1939 |
+ |
if (!g.casHash(MOVED|LOCKED, MOVED)) { |
1940 |
+ |
g.hash = MOVED; |
1941 |
+ |
synchronized (g) { g.notifyAll(); } |
1942 |
+ |
} |
1943 |
+ |
} |
1944 |
+ |
} |
1945 |
+ |
else if ((fh = f.hash) == MOVED) { |
1946 |
+ |
Object fk = f.key; |
1947 |
+ |
if (fk instanceof TreeBin) { |
1948 |
+ |
TreeBin t = (TreeBin)fk; |
1949 |
+ |
boolean validated = false; |
1950 |
+ |
t.acquire(0); |
1951 |
+ |
try { |
1952 |
+ |
if (tabAt(tab, i) == f) { |
1953 |
+ |
validated = true; |
1954 |
+ |
splitTreeBin(nextTab, i, t); |
1955 |
+ |
setTabAt(tab, i, fwd); |
1956 |
+ |
} |
1957 |
+ |
} finally { |
1958 |
+ |
t.release(0); |
1959 |
+ |
} |
1960 |
+ |
if (!validated) |
1961 |
+ |
continue; |
1962 |
+ |
} |
1963 |
+ |
} |
1964 |
+ |
else if ((fh & LOCKED) == 0 && f.casHash(fh, fh|LOCKED)) { |
1965 |
+ |
boolean validated = false; |
1966 |
+ |
try { // split to lo and hi lists; copying as needed |
1967 |
+ |
if (tabAt(tab, i) == f) { |
1968 |
+ |
validated = true; |
1969 |
+ |
splitBin(nextTab, i, f); |
1970 |
+ |
setTabAt(tab, i, fwd); |
1971 |
+ |
} |
1972 |
+ |
} finally { |
1973 |
+ |
if (!f.casHash(fh | LOCKED, fh)) { |
1974 |
+ |
f.hash = fh; |
1975 |
+ |
synchronized (f) { f.notifyAll(); }; |
1976 |
+ |
} |
1977 |
+ |
} |
1978 |
+ |
if (!validated) |
1979 |
+ |
continue; |
1980 |
+ |
} |
1981 |
+ |
else { |
1982 |
+ |
if (buffer == null) // initialize buffer for revisits |
1983 |
+ |
buffer = new int[TRANSFER_BUFFER_SIZE]; |
1984 |
+ |
if (bin < 0 && bufferIndex > 0) { |
1985 |
+ |
int j = buffer[--bufferIndex]; |
1986 |
+ |
buffer[bufferIndex] = i; |
1987 |
+ |
i = j; // swap with another bin |
1988 |
+ |
continue; |
1989 |
+ |
} |
1990 |
+ |
if (bin < 0 || nbuffered >= TRANSFER_BUFFER_SIZE) { |
1991 |
+ |
f.tryAwaitLock(tab, i); |
1992 |
+ |
continue; // no other options -- block |
1993 |
+ |
} |
1994 |
+ |
if (rev == null) // initialize reverse-forwarder |
1995 |
+ |
rev = new Node(MOVED, tab, null, null); |
1996 |
+ |
if (tabAt(tab, i) != f || (f.hash & LOCKED) == 0) |
1997 |
+ |
continue; // recheck before adding to list |
1998 |
+ |
buffer[nbuffered++] = i; |
1999 |
+ |
setTabAt(nextTab, i, rev); // install place-holders |
2000 |
+ |
setTabAt(nextTab, i + n, rev); |
2001 |
+ |
} |
2002 |
+ |
|
2003 |
+ |
if (bin > 0) |
2004 |
+ |
i = --bin; |
2005 |
+ |
else if (buffer != null && nbuffered > 0) { |
2006 |
+ |
bin = -1; |
2007 |
+ |
i = buffer[bufferIndex = --nbuffered]; |
2008 |
+ |
} |
2009 |
+ |
else |
2010 |
+ |
return nextTab; |
2011 |
+ |
} |
2012 |
+ |
} |
2013 |
+ |
|
2014 |
+ |
/** |
2015 |
+ |
* Split a normal bin with list headed by e into lo and hi parts; |
2016 |
+ |
* install in given table |
2017 |
+ |
*/ |
2018 |
+ |
private static void splitBin(Node[] nextTab, int i, Node e) { |
2019 |
+ |
int bit = nextTab.length >>> 1; // bit to split on |
2020 |
+ |
int runBit = e.hash & bit; |
2021 |
+ |
Node lastRun = e, lo = null, hi = null; |
2022 |
+ |
for (Node p = e.next; p != null; p = p.next) { |
2023 |
+ |
int b = p.hash & bit; |
2024 |
+ |
if (b != runBit) { |
2025 |
+ |
runBit = b; |
2026 |
+ |
lastRun = p; |
2027 |
+ |
} |
2028 |
+ |
} |
2029 |
+ |
if (runBit == 0) |
2030 |
+ |
lo = lastRun; |
2031 |
+ |
else |
2032 |
+ |
hi = lastRun; |
2033 |
+ |
for (Node p = e; p != lastRun; p = p.next) { |
2034 |
+ |
int ph = p.hash & HASH_BITS; |
2035 |
+ |
Object pk = p.key, pv = p.val; |
2036 |
+ |
if ((ph & bit) == 0) |
2037 |
+ |
lo = new Node(ph, pk, pv, lo); |
2038 |
+ |
else |
2039 |
+ |
hi = new Node(ph, pk, pv, hi); |
2040 |
+ |
} |
2041 |
+ |
setTabAt(nextTab, i, lo); |
2042 |
+ |
setTabAt(nextTab, i + bit, hi); |
2043 |
+ |
} |
2044 |
+ |
|
2045 |
+ |
/** |
2046 |
+ |
* Split a tree bin into lo and hi parts; install in given table |
2047 |
+ |
*/ |
2048 |
+ |
private static void splitTreeBin(Node[] nextTab, int i, TreeBin t) { |
2049 |
+ |
int bit = nextTab.length >>> 1; |
2050 |
+ |
TreeBin lt = new TreeBin(); |
2051 |
+ |
TreeBin ht = new TreeBin(); |
2052 |
+ |
int lc = 0, hc = 0; |
2053 |
+ |
for (Node e = t.first; e != null; e = e.next) { |
2054 |
+ |
int h = e.hash & HASH_BITS; |
2055 |
+ |
Object k = e.key, v = e.val; |
2056 |
+ |
if ((h & bit) == 0) { |
2057 |
+ |
++lc; |
2058 |
+ |
lt.putTreeNode(h, k, v); |
2059 |
+ |
} |
2060 |
+ |
else { |
2061 |
+ |
++hc; |
2062 |
+ |
ht.putTreeNode(h, k, v); |
2063 |
+ |
} |
2064 |
+ |
} |
2065 |
+ |
Node ln, hn; // throw away trees if too small |
2066 |
+ |
if (lc <= (TREE_THRESHOLD >>> 1)) { |
2067 |
+ |
ln = null; |
2068 |
+ |
for (Node p = lt.first; p != null; p = p.next) |
2069 |
+ |
ln = new Node(p.hash, p.key, p.val, ln); |
2070 |
+ |
} |
2071 |
+ |
else |
2072 |
+ |
ln = new Node(MOVED, lt, null, null); |
2073 |
+ |
setTabAt(nextTab, i, ln); |
2074 |
+ |
if (hc <= (TREE_THRESHOLD >>> 1)) { |
2075 |
+ |
hn = null; |
2076 |
+ |
for (Node p = ht.first; p != null; p = p.next) |
2077 |
+ |
hn = new Node(p.hash, p.key, p.val, hn); |
2078 |
+ |
} |
2079 |
+ |
else |
2080 |
+ |
hn = new Node(MOVED, ht, null, null); |
2081 |
+ |
setTabAt(nextTab, i + bit, hn); |
2082 |
+ |
} |
2083 |
+ |
|
2084 |
|
/** |
2085 |
< |
* Implementation for clear. Steps through each bin, removing all nodes. |
2085 |
> |
* Implementation for clear. Steps through each bin, removing all |
2086 |
> |
* nodes. |
2087 |
|
*/ |
2088 |
|
private final void internalClear() { |
2089 |
|
long delta = 0L; // negative number of deletions |
2090 |
|
int i = 0; |
2091 |
|
Node[] tab = table; |
2092 |
|
while (tab != null && i < tab.length) { |
2093 |
< |
Node e = tabAt(tab, i); |
2094 |
< |
if (e == null) |
2093 |
> |
int fh; Object fk; |
2094 |
> |
Node f = tabAt(tab, i); |
2095 |
> |
if (f == null) |
2096 |
|
++i; |
2097 |
< |
else if (e.hash < 0) |
2098 |
< |
tab = (Node[])e.key; |
2099 |
< |
else { |
2100 |
< |
boolean validated = false; |
2101 |
< |
synchronized (e) { |
2102 |
< |
if (tabAt(tab, i) == e) { |
2103 |
< |
validated = true; |
2104 |
< |
Node en; |
719 |
< |
do { |
720 |
< |
en = e.next; |
721 |
< |
if (e.val != null) { // currently always true |
722 |
< |
e.val = null; |
2097 |
> |
else if ((fh = f.hash) == MOVED) { |
2098 |
> |
if ((fk = f.key) instanceof TreeBin) { |
2099 |
> |
TreeBin t = (TreeBin)fk; |
2100 |
> |
t.acquire(0); |
2101 |
> |
try { |
2102 |
> |
if (tabAt(tab, i) == f) { |
2103 |
> |
for (Node p = t.first; p != null; p = p.next) { |
2104 |
> |
p.val = null; |
2105 |
|
--delta; |
2106 |
|
} |
2107 |
< |
} while ((e = en) != null); |
2107 |
> |
t.first = null; |
2108 |
> |
t.root = null; |
2109 |
> |
++i; |
2110 |
> |
} |
2111 |
> |
} finally { |
2112 |
> |
t.release(0); |
2113 |
> |
} |
2114 |
> |
} |
2115 |
> |
else |
2116 |
> |
tab = (Node[])fk; |
2117 |
> |
} |
2118 |
> |
else if ((fh & LOCKED) != 0) { |
2119 |
> |
counter.add(delta); // opportunistically update count |
2120 |
> |
delta = 0L; |
2121 |
> |
f.tryAwaitLock(tab, i); |
2122 |
> |
} |
2123 |
> |
else if (f.casHash(fh, fh | LOCKED)) { |
2124 |
> |
try { |
2125 |
> |
if (tabAt(tab, i) == f) { |
2126 |
> |
for (Node e = f; e != null; e = e.next) { |
2127 |
> |
e.val = null; |
2128 |
> |
--delta; |
2129 |
> |
} |
2130 |
|
setTabAt(tab, i, null); |
2131 |
+ |
++i; |
2132 |
+ |
} |
2133 |
+ |
} finally { |
2134 |
+ |
if (!f.casHash(fh | LOCKED, fh)) { |
2135 |
+ |
f.hash = fh; |
2136 |
+ |
synchronized (f) { f.notifyAll(); }; |
2137 |
|
} |
2138 |
|
} |
729 |
– |
if (validated) |
730 |
– |
++i; |
2139 |
|
} |
2140 |
|
} |
2141 |
< |
counter.add(delta); |
2141 |
> |
if (delta != 0) |
2142 |
> |
counter.add(delta); |
2143 |
|
} |
2144 |
|
|
2145 |
|
/* ----------------Table Traversal -------------- */ |
2150 |
|
* |
2151 |
|
* At each step, the iterator snapshots the key ("nextKey") and |
2152 |
|
* value ("nextVal") of a valid node (i.e., one that, at point of |
2153 |
< |
* snapshot, has a nonnull user value). Because val fields can |
2153 |
> |
* snapshot, has a non-null user value). Because val fields can |
2154 |
|
* change (including to null, indicating deletion), field nextVal |
2155 |
|
* might not be accurate at point of use, but still maintains the |
2156 |
|
* weak consistency property of holding a value that was once |
2157 |
|
* valid. |
2158 |
|
* |
2159 |
|
* Internal traversals directly access these fields, as in: |
2160 |
< |
* {@code while (it.next != null) { process(nextKey); it.advance(); }} |
2160 |
> |
* {@code while (it.advance() != null) { process(it.nextKey); }} |
2161 |
|
* |
2162 |
< |
* Exported iterators (subclasses of ViewIterator) extract key, |
2163 |
< |
* value, or key-value pairs as return values of Iterator.next(), |
2164 |
< |
* and encapulate the it.next check as hasNext(); |
2165 |
< |
* |
2166 |
< |
* The iterator visits each valid node that was reachable upon |
2167 |
< |
* iterator construction once. It might miss some that were added |
2168 |
< |
* to a bin after the bin was visited, which is OK wrt consistency |
2169 |
< |
* guarantees. Maintaining this property in the face of possible |
2170 |
< |
* ongoing resizes requires a fair amount of bookkeeping state |
2171 |
< |
* that is difficult to optimize away amidst volatile accesses. |
2172 |
< |
* Even so, traversal maintains reasonable throughput. |
2162 |
> |
* Exported iterators must track whether the iterator has advanced |
2163 |
> |
* (in hasNext vs next) (by setting/checking/nulling field |
2164 |
> |
* nextVal), and then extract key, value, or key-value pairs as |
2165 |
> |
* return values of next(). |
2166 |
> |
* |
2167 |
> |
* The iterator visits once each still-valid node that was |
2168 |
> |
* reachable upon iterator construction. It might miss some that |
2169 |
> |
* were added to a bin after the bin was visited, which is OK wrt |
2170 |
> |
* consistency guarantees. Maintaining this property in the face |
2171 |
> |
* of possible ongoing resizes requires a fair amount of |
2172 |
> |
* bookkeeping state that is difficult to optimize away amidst |
2173 |
> |
* volatile accesses. Even so, traversal maintains reasonable |
2174 |
> |
* throughput. |
2175 |
|
* |
2176 |
|
* Normally, iteration proceeds bin-by-bin traversing lists. |
2177 |
|
* However, if the table has been resized, then all future steps |
2180 |
|
* paranoically cope with potential sharing by users of iterators |
2181 |
|
* across threads, iteration terminates if a bounds checks fails |
2182 |
|
* for a table read. |
772 |
– |
* |
773 |
– |
* The range-based constructor enables creation of parallel |
774 |
– |
* range-splitting traversals. (Not yet implemented.) |
2183 |
|
*/ |
2184 |
< |
static class InternalIterator { |
2184 |
> |
static class InternalIterator<K,V> { |
2185 |
> |
final ConcurrentHashMapV8<K, V> map; |
2186 |
|
Node next; // the next entry to use |
2187 |
|
Node last; // the last entry used |
2188 |
|
Object nextKey; // cached key field of next |
2190 |
|
Node[] tab; // current table; updated if resized |
2191 |
|
int index; // index of bin to use next |
2192 |
|
int baseIndex; // current index of initial table |
2193 |
< |
final int baseLimit; // index bound for initial table |
2193 |
> |
int baseLimit; // index bound for initial table |
2194 |
|
final int baseSize; // initial table size |
2195 |
|
|
2196 |
|
/** Creates iterator for all entries in the table. */ |
2197 |
< |
InternalIterator(Node[] tab) { |
2198 |
< |
this.tab = tab; |
2197 |
> |
InternalIterator(ConcurrentHashMapV8<K, V> map) { |
2198 |
> |
this.tab = (this.map = map).table; |
2199 |
|
baseLimit = baseSize = (tab == null) ? 0 : tab.length; |
791 |
– |
index = baseIndex = 0; |
792 |
– |
next = null; |
793 |
– |
advance(); |
794 |
– |
} |
795 |
– |
|
796 |
– |
/** Creates iterator for the given range of the table */ |
797 |
– |
InternalIterator(Node[] tab, int lo, int hi) { |
798 |
– |
this.tab = tab; |
799 |
– |
baseSize = (tab == null) ? 0 : tab.length; |
800 |
– |
baseLimit = (hi <= baseSize)? hi : baseSize; |
801 |
– |
index = baseIndex = lo; |
802 |
– |
next = null; |
803 |
– |
advance(); |
2200 |
|
} |
2201 |
|
|
2202 |
< |
/** Advances next. See above for explanation. */ |
2203 |
< |
final void advance() { |
2202 |
> |
/** Creates iterator for clone() and split() methods */ |
2203 |
> |
InternalIterator(InternalIterator<K,V> it, boolean split) { |
2204 |
> |
this.map = it.map; |
2205 |
> |
this.tab = it.tab; |
2206 |
> |
this.baseSize = it.baseSize; |
2207 |
> |
int lo = it.baseIndex; |
2208 |
> |
int hi = this.baseLimit = it.baseLimit; |
2209 |
> |
this.index = this.baseIndex = |
2210 |
> |
(split) ? (it.baseLimit = (lo + hi + 1) >>> 1) : lo; |
2211 |
> |
} |
2212 |
> |
|
2213 |
> |
/** |
2214 |
> |
* Advances next; returns nextVal or null if terminated |
2215 |
> |
* See above for explanation. |
2216 |
> |
*/ |
2217 |
> |
final Object advance() { |
2218 |
|
Node e = last = next; |
2219 |
+ |
Object ev = null; |
2220 |
|
outer: do { |
2221 |
< |
if (e != null) // pass used or skipped node |
2221 |
> |
if (e != null) // advance past used/skipped node |
2222 |
|
e = e.next; |
2223 |
< |
while (e == null) { // get to next non-null bin |
2224 |
< |
Node[] t; int b, i, n; // checks must use locals |
2223 |
> |
while (e == null) { // get to next non-null bin |
2224 |
> |
Node[] t; int b, i, n; Object ek; // checks must use locals |
2225 |
|
if ((b = baseIndex) >= baseLimit || (i = index) < 0 || |
2226 |
|
(t = tab) == null || i >= (n = t.length)) |
2227 |
|
break outer; |
2228 |
< |
else if ((e = tabAt(t, i)) != null && e.hash < 0) |
2229 |
< |
tab = (Node[])e.key; // restarts due to null val |
2230 |
< |
else // visit upper slots if present |
2231 |
< |
index = (i += baseSize) < n ? i : (baseIndex = b + 1); |
2228 |
> |
else if ((e = tabAt(t, i)) != null && e.hash == MOVED) { |
2229 |
> |
if ((ek = e.key) instanceof TreeBin) |
2230 |
> |
e = ((TreeBin)ek).first; |
2231 |
> |
else { |
2232 |
> |
tab = (Node[])ek; |
2233 |
> |
continue; // restarts due to null val |
2234 |
> |
} |
2235 |
> |
} // visit upper slots if present |
2236 |
> |
index = (i += baseSize) < n ? i : (baseIndex = b + 1); |
2237 |
|
} |
2238 |
|
nextKey = e.key; |
2239 |
< |
} while ((nextVal = e.val) == null); // skip deleted or special nodes |
2239 |
> |
} while ((ev = e.val) == null); // skip deleted or special nodes |
2240 |
|
next = e; |
2241 |
+ |
return nextVal = ev; |
2242 |
+ |
} |
2243 |
+ |
|
2244 |
+ |
public final void remove() { |
2245 |
+ |
if (nextVal == null) |
2246 |
+ |
advance(); |
2247 |
+ |
Node e = last; |
2248 |
+ |
if (e == null) |
2249 |
+ |
throw new IllegalStateException(); |
2250 |
+ |
last = null; |
2251 |
+ |
map.remove(e.key); |
2252 |
+ |
} |
2253 |
+ |
|
2254 |
+ |
public final boolean hasNext() { |
2255 |
+ |
return nextVal != null || advance() != null; |
2256 |
|
} |
2257 |
+ |
|
2258 |
+ |
public final boolean hasMoreElements() { return hasNext(); } |
2259 |
|
} |
2260 |
|
|
2261 |
|
/* ---------------- Public operations -------------- */ |
2262 |
|
|
2263 |
|
/** |
2264 |
< |
* Creates a new, empty map with the specified initial |
832 |
< |
* capacity, load factor and concurrency level. |
833 |
< |
* |
834 |
< |
* @param initialCapacity the initial capacity. The implementation |
835 |
< |
* performs internal sizing to accommodate this many elements. |
836 |
< |
* @param loadFactor the load factor threshold, used to control resizing. |
837 |
< |
* Resizing may be performed when the average number of elements per |
838 |
< |
* bin exceeds this threshold. |
839 |
< |
* @param concurrencyLevel the estimated number of concurrently |
840 |
< |
* updating threads. The implementation may use this value as |
841 |
< |
* a sizing hint. |
842 |
< |
* @throws IllegalArgumentException if the initial capacity is |
843 |
< |
* negative or the load factor or concurrencyLevel are |
844 |
< |
* nonpositive. |
2264 |
> |
* Creates a new, empty map with the default initial table size (16), |
2265 |
|
*/ |
2266 |
< |
public ConcurrentHashMapV8(int initialCapacity, |
847 |
< |
float loadFactor, int concurrencyLevel) { |
848 |
< |
if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0) |
849 |
< |
throw new IllegalArgumentException(); |
850 |
< |
int cap = tableSizeFor(initialCapacity); |
2266 |
> |
public ConcurrentHashMapV8() { |
2267 |
|
this.counter = new LongAdder(); |
852 |
– |
this.loadFactor = loadFactor; |
853 |
– |
this.targetCapacity = cap; |
2268 |
|
} |
2269 |
|
|
2270 |
|
/** |
2271 |
< |
* Creates a new, empty map with the specified initial capacity |
2272 |
< |
* and load factor and with the default concurrencyLevel (16). |
2271 |
> |
* Creates a new, empty map with an initial table size |
2272 |
> |
* accommodating the specified number of elements without the need |
2273 |
> |
* to dynamically resize. |
2274 |
|
* |
2275 |
|
* @param initialCapacity The implementation performs internal |
2276 |
|
* sizing to accommodate this many elements. |
862 |
– |
* @param loadFactor the load factor threshold, used to control resizing. |
863 |
– |
* Resizing may be performed when the average number of elements per |
864 |
– |
* bin exceeds this threshold. |
2277 |
|
* @throws IllegalArgumentException if the initial capacity of |
2278 |
< |
* elements is negative or the load factor is nonpositive |
867 |
< |
* |
868 |
< |
* @since 1.6 |
2278 |
> |
* elements is negative |
2279 |
|
*/ |
2280 |
< |
public ConcurrentHashMapV8(int initialCapacity, float loadFactor) { |
2281 |
< |
this(initialCapacity, loadFactor, DEFAULT_CONCURRENCY_LEVEL); |
2280 |
> |
public ConcurrentHashMapV8(int initialCapacity) { |
2281 |
> |
if (initialCapacity < 0) |
2282 |
> |
throw new IllegalArgumentException(); |
2283 |
> |
int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ? |
2284 |
> |
MAXIMUM_CAPACITY : |
2285 |
> |
tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1)); |
2286 |
> |
this.counter = new LongAdder(); |
2287 |
> |
this.sizeCtl = cap; |
2288 |
|
} |
2289 |
|
|
2290 |
|
/** |
2291 |
< |
* Creates a new, empty map with the specified initial capacity, |
876 |
< |
* and with default load factor (0.75) and concurrencyLevel (16). |
2291 |
> |
* Creates a new map with the same mappings as the given map. |
2292 |
|
* |
2293 |
< |
* @param initialCapacity the initial capacity. The implementation |
879 |
< |
* performs internal sizing to accommodate this many elements. |
880 |
< |
* @throws IllegalArgumentException if the initial capacity of |
881 |
< |
* elements is negative. |
2293 |
> |
* @param m the map |
2294 |
|
*/ |
2295 |
< |
public ConcurrentHashMapV8(int initialCapacity) { |
2296 |
< |
this(initialCapacity, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL); |
2295 |
> |
public ConcurrentHashMapV8(Map<? extends K, ? extends V> m) { |
2296 |
> |
this.counter = new LongAdder(); |
2297 |
> |
this.sizeCtl = DEFAULT_CAPACITY; |
2298 |
> |
internalPutAll(m); |
2299 |
|
} |
2300 |
|
|
2301 |
|
/** |
2302 |
< |
* Creates a new, empty map with a default initial capacity (16), |
2303 |
< |
* load factor (0.75) and concurrencyLevel (16). |
2302 |
> |
* Creates a new, empty map with an initial table size based on |
2303 |
> |
* the given number of elements ({@code initialCapacity}) and |
2304 |
> |
* initial table density ({@code loadFactor}). |
2305 |
> |
* |
2306 |
> |
* @param initialCapacity the initial capacity. The implementation |
2307 |
> |
* performs internal sizing to accommodate this many elements, |
2308 |
> |
* given the specified load factor. |
2309 |
> |
* @param loadFactor the load factor (table density) for |
2310 |
> |
* establishing the initial table size |
2311 |
> |
* @throws IllegalArgumentException if the initial capacity of |
2312 |
> |
* elements is negative or the load factor is nonpositive |
2313 |
> |
* |
2314 |
> |
* @since 1.6 |
2315 |
|
*/ |
2316 |
< |
public ConcurrentHashMapV8() { |
2317 |
< |
this(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL); |
2316 |
> |
public ConcurrentHashMapV8(int initialCapacity, float loadFactor) { |
2317 |
> |
this(initialCapacity, loadFactor, 1); |
2318 |
|
} |
2319 |
|
|
2320 |
|
/** |
2321 |
< |
* Creates a new map with the same mappings as the given map. |
2322 |
< |
* The map is created with a capacity of 1.5 times the number |
2323 |
< |
* of mappings in the given map or 16 (whichever is greater), |
2324 |
< |
* and a default load factor (0.75) and concurrencyLevel (16). |
2321 |
> |
* Creates a new, empty map with an initial table size based on |
2322 |
> |
* the given number of elements ({@code initialCapacity}), table |
2323 |
> |
* density ({@code loadFactor}), and number of concurrently |
2324 |
> |
* updating threads ({@code concurrencyLevel}). |
2325 |
|
* |
2326 |
< |
* @param m the map |
2326 |
> |
* @param initialCapacity the initial capacity. The implementation |
2327 |
> |
* performs internal sizing to accommodate this many elements, |
2328 |
> |
* given the specified load factor. |
2329 |
> |
* @param loadFactor the load factor (table density) for |
2330 |
> |
* establishing the initial table size |
2331 |
> |
* @param concurrencyLevel the estimated number of concurrently |
2332 |
> |
* updating threads. The implementation may use this value as |
2333 |
> |
* a sizing hint. |
2334 |
> |
* @throws IllegalArgumentException if the initial capacity is |
2335 |
> |
* negative or the load factor or concurrencyLevel are |
2336 |
> |
* nonpositive |
2337 |
|
*/ |
2338 |
< |
public ConcurrentHashMapV8(Map<? extends K, ? extends V> m) { |
2339 |
< |
this(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL); |
2340 |
< |
putAll(m); |
2338 |
> |
public ConcurrentHashMapV8(int initialCapacity, |
2339 |
> |
float loadFactor, int concurrencyLevel) { |
2340 |
> |
if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0) |
2341 |
> |
throw new IllegalArgumentException(); |
2342 |
> |
if (initialCapacity < concurrencyLevel) // Use at least as many bins |
2343 |
> |
initialCapacity = concurrencyLevel; // as estimated threads |
2344 |
> |
long size = (long)(1.0 + (long)initialCapacity / loadFactor); |
2345 |
> |
int cap = ((size >= (long)MAXIMUM_CAPACITY) ? |
2346 |
> |
MAXIMUM_CAPACITY: tableSizeFor((int)size)); |
2347 |
> |
this.counter = new LongAdder(); |
2348 |
> |
this.sizeCtl = cap; |
2349 |
|
} |
2350 |
|
|
2351 |
|
/** |
2360 |
|
*/ |
2361 |
|
public int size() { |
2362 |
|
long n = counter.sum(); |
2363 |
< |
return ((n < 0L)? 0 : |
2364 |
< |
(n > (long)Integer.MAX_VALUE)? Integer.MAX_VALUE : |
2363 |
> |
return ((n < 0L) ? 0 : |
2364 |
> |
(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE : |
2365 |
|
(int)n); |
2366 |
|
} |
2367 |
|
|
2368 |
+ |
final long longSize() { // accurate version of size needed for views |
2369 |
+ |
long n = counter.sum(); |
2370 |
+ |
return (n < 0L) ? 0L : n; |
2371 |
+ |
} |
2372 |
+ |
|
2373 |
|
/** |
2374 |
|
* Returns the value to which the specified key is mapped, |
2375 |
|
* or {@code null} if this map contains no mapping for the key. |
2394 |
|
* @param key possible key |
2395 |
|
* @return {@code true} if and only if the specified object |
2396 |
|
* is a key in this table, as determined by the |
2397 |
< |
* {@code equals} method; {@code false} otherwise. |
2397 |
> |
* {@code equals} method; {@code false} otherwise |
2398 |
|
* @throws NullPointerException if the specified key is null |
2399 |
|
*/ |
2400 |
|
public boolean containsKey(Object key) { |
2417 |
|
if (value == null) |
2418 |
|
throw new NullPointerException(); |
2419 |
|
Object v; |
2420 |
< |
InternalIterator it = new InternalIterator(table); |
2421 |
< |
while (it.next != null) { |
2422 |
< |
if ((v = it.nextVal) == value || value.equals(v)) |
2420 |
> |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
2421 |
> |
while ((v = it.advance()) != null) { |
2422 |
> |
if (v == value || value.equals(v)) |
2423 |
|
return true; |
976 |
– |
it.advance(); |
2424 |
|
} |
2425 |
|
return false; |
2426 |
|
} |
2461 |
|
public V put(K key, V value) { |
2462 |
|
if (key == null || value == null) |
2463 |
|
throw new NullPointerException(); |
2464 |
< |
return (V)internalPut(key, value, true); |
2464 |
> |
return (V)internalPut(key, value); |
2465 |
|
} |
2466 |
|
|
2467 |
|
/** |
2475 |
|
public V putIfAbsent(K key, V value) { |
2476 |
|
if (key == null || value == null) |
2477 |
|
throw new NullPointerException(); |
2478 |
< |
return (V)internalPut(key, value, false); |
2478 |
> |
return (V)internalPutIfAbsent(key, value); |
2479 |
|
} |
2480 |
|
|
2481 |
|
/** |
2486 |
|
* @param m mappings to be stored in this map |
2487 |
|
*/ |
2488 |
|
public void putAll(Map<? extends K, ? extends V> m) { |
2489 |
< |
if (m == null) |
1043 |
< |
throw new NullPointerException(); |
1044 |
< |
/* |
1045 |
< |
* If uninitialized, try to adjust targetCapacity to |
1046 |
< |
* accommodate the given number of elements. |
1047 |
< |
*/ |
1048 |
< |
if (table == null) { |
1049 |
< |
int size = m.size(); |
1050 |
< |
int cap = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY : |
1051 |
< |
tableSizeFor(size + (size >>> 1)); |
1052 |
< |
if (cap > targetCapacity) |
1053 |
< |
targetCapacity = cap; |
1054 |
< |
} |
1055 |
< |
for (Map.Entry<? extends K, ? extends V> e : m.entrySet()) |
1056 |
< |
put(e.getKey(), e.getValue()); |
2489 |
> |
internalPutAll(m); |
2490 |
|
} |
2491 |
|
|
2492 |
|
/** |
2493 |
|
* If the specified key is not already associated with a value, |
2494 |
< |
* computes its value using the given mappingFunction, and if |
2495 |
< |
* non-null, enters it into the map. This is equivalent to |
2496 |
< |
* <pre> {@code |
2494 |
> |
* computes its value using the given mappingFunction and enters |
2495 |
> |
* it into the map unless null. This is equivalent to |
2496 |
> |
* <pre> {@code |
2497 |
|
* if (map.containsKey(key)) |
2498 |
|
* return map.get(key); |
2499 |
|
* value = mappingFunction.map(key); |
2501 |
|
* map.put(key, value); |
2502 |
|
* return value;}</pre> |
2503 |
|
* |
2504 |
< |
* except that the action is performed atomically. Some attempted |
2505 |
< |
* update operations on this map by other threads may be blocked |
2506 |
< |
* while computation is in progress, so the computation should be |
2507 |
< |
* short and simple, and must not attempt to update any other |
2508 |
< |
* mappings of this Map. The most appropriate usage is to |
2504 |
> |
* except that the action is performed atomically. If the |
2505 |
> |
* function returns {@code null} no mapping is recorded. If the |
2506 |
> |
* function itself throws an (unchecked) exception, the exception |
2507 |
> |
* is rethrown to its caller, and no mapping is recorded. Some |
2508 |
> |
* attempted update operations on this map by other threads may be |
2509 |
> |
* blocked while computation is in progress, so the computation |
2510 |
> |
* should be short and simple, and must not attempt to update any |
2511 |
> |
* other mappings of this Map. The most appropriate usage is to |
2512 |
|
* construct a new object serving as an initial mapped value, or |
2513 |
|
* memoized result, as in: |
2514 |
+ |
* |
2515 |
|
* <pre> {@code |
2516 |
|
* map.computeIfAbsent(key, new MappingFunction<K, V>() { |
2517 |
|
* public V map(K k) { return new Value(f(k)); }});}</pre> |
2519 |
|
* @param key key with which the specified value is to be associated |
2520 |
|
* @param mappingFunction the function to compute a value |
2521 |
|
* @return the current (existing or computed) value associated with |
2522 |
< |
* the specified key, or {@code null} if the computation |
1086 |
< |
* returned {@code null}. |
2522 |
> |
* the specified key, or null if the computed value is null. |
2523 |
|
* @throws NullPointerException if the specified key or mappingFunction |
2524 |
< |
* is null, |
2524 |
> |
* is null |
2525 |
|
* @throws IllegalStateException if the computation detectably |
2526 |
|
* attempts a recursive update to this map that would |
2527 |
< |
* otherwise never complete. |
2527 |
> |
* otherwise never complete |
2528 |
|
* @throws RuntimeException or Error if the mappingFunction does so, |
2529 |
< |
* in which case the mapping is left unestablished. |
2529 |
> |
* in which case the mapping is left unestablished |
2530 |
|
*/ |
2531 |
+ |
@SuppressWarnings("unchecked") |
2532 |
|
public V computeIfAbsent(K key, MappingFunction<? super K, ? extends V> mappingFunction) { |
2533 |
|
if (key == null || mappingFunction == null) |
2534 |
|
throw new NullPointerException(); |
2535 |
< |
return internalCompute(key, mappingFunction, false); |
2535 |
> |
return (V)internalComputeIfAbsent(key, mappingFunction); |
2536 |
|
} |
2537 |
|
|
2538 |
|
/** |
2539 |
< |
* Computes the value associated with the given key using the given |
2540 |
< |
* mappingFunction, and if non-null, enters it into the map. This |
2541 |
< |
* is equivalent to |
2539 |
> |
* Computes a new mapping value given a key and |
2540 |
> |
* its current mapped value (or {@code null} if there is no current |
2541 |
> |
* mapping). This is equivalent to |
2542 |
|
* <pre> {@code |
2543 |
< |
* value = mappingFunction.map(key); |
2544 |
< |
* if (value != null) |
2545 |
< |
* map.put(key, value); |
2546 |
< |
* else |
2547 |
< |
* value = map.get(key); |
2548 |
< |
* return value;}</pre> |
2549 |
< |
* |
2550 |
< |
* except that the action is performed atomically. Some attempted |
2551 |
< |
* update operations on this map by other threads may be blocked |
2552 |
< |
* while computation is in progress, so the computation should be |
2553 |
< |
* short and simple, and must not attempt to update any other |
2554 |
< |
* mappings of this Map. |
2543 |
> |
* value = remappingFunction.remap(key, map.get(key)); |
2544 |
> |
* if (value != null) |
2545 |
> |
* map.put(key, value); |
2546 |
> |
* else |
2547 |
> |
* map.remove(key); |
2548 |
> |
* }</pre> |
2549 |
> |
* |
2550 |
> |
* except that the action is performed atomically. If the |
2551 |
> |
* function returns {@code null}, the mapping is removed. If the |
2552 |
> |
* function itself throws an (unchecked) exception, the exception |
2553 |
> |
* is rethrown to its caller, and the current mapping is left |
2554 |
> |
* unchanged. Some attempted update operations on this map by |
2555 |
> |
* other threads may be blocked while computation is in progress, |
2556 |
> |
* so the computation should be short and simple, and must not |
2557 |
> |
* attempt to update any other mappings of this Map. For example, |
2558 |
> |
* to either create or append new messages to a value mapping: |
2559 |
> |
* |
2560 |
> |
* <pre> {@code |
2561 |
> |
* Map<Key, String> map = ...; |
2562 |
> |
* final String msg = ...; |
2563 |
> |
* map.compute(key, new RemappingFunction<Key, String>() { |
2564 |
> |
* public String remap(Key k, String v) { |
2565 |
> |
* return (v == null) ? msg : v + msg;});}}</pre> |
2566 |
|
* |
2567 |
|
* @param key key with which the specified value is to be associated |
2568 |
< |
* @param mappingFunction the function to compute a value |
2569 |
< |
* @return the current value associated with |
2570 |
< |
* the specified key, or {@code null} if the computation |
2571 |
< |
* returned {@code null} and the value was not otherwise present. |
2572 |
< |
* @throws NullPointerException if the specified key or mappingFunction |
1125 |
< |
* is null, |
2568 |
> |
* @param remappingFunction the function to compute a value |
2569 |
> |
* @return the new value associated with |
2570 |
> |
* the specified key, or null if none. |
2571 |
> |
* @throws NullPointerException if the specified key or remappingFunction |
2572 |
> |
* is null |
2573 |
|
* @throws IllegalStateException if the computation detectably |
2574 |
|
* attempts a recursive update to this map that would |
2575 |
< |
* otherwise never complete. |
2576 |
< |
* @throws RuntimeException or Error if the mappingFunction does so, |
2577 |
< |
* in which case the mapping is unchanged. |
2575 |
> |
* otherwise never complete |
2576 |
> |
* @throws RuntimeException or Error if the remappingFunction does so, |
2577 |
> |
* in which case the mapping is unchanged |
2578 |
|
*/ |
2579 |
< |
public V compute(K key, MappingFunction<? super K, ? extends V> mappingFunction) { |
2580 |
< |
if (key == null || mappingFunction == null) |
2579 |
> |
@SuppressWarnings("unchecked") |
2580 |
> |
public V compute(K key, RemappingFunction<? super K, V> remappingFunction) { |
2581 |
> |
if (key == null || remappingFunction == null) |
2582 |
|
throw new NullPointerException(); |
2583 |
< |
return internalCompute(key, mappingFunction, true); |
2583 |
> |
return (V)internalCompute(key, remappingFunction); |
2584 |
|
} |
2585 |
|
|
2586 |
|
/** |
2728 |
|
} |
2729 |
|
|
2730 |
|
/** |
2731 |
+ |
* Returns a partionable iterator of the keys in this map. |
2732 |
+ |
* |
2733 |
+ |
* @return a partionable iterator of the keys in this map |
2734 |
+ |
*/ |
2735 |
+ |
public Spliterator<K> keySpliterator() { |
2736 |
+ |
return new KeyIterator<K,V>(this); |
2737 |
+ |
} |
2738 |
+ |
|
2739 |
+ |
/** |
2740 |
+ |
* Returns a partionable iterator of the values in this map. |
2741 |
+ |
* |
2742 |
+ |
* @return a partionable iterator of the values in this map |
2743 |
+ |
*/ |
2744 |
+ |
public Spliterator<V> valueSpliterator() { |
2745 |
+ |
return new ValueIterator<K,V>(this); |
2746 |
+ |
} |
2747 |
+ |
|
2748 |
+ |
/** |
2749 |
+ |
* Returns a partionable iterator of the entries in this map. |
2750 |
+ |
* |
2751 |
+ |
* @return a partionable iterator of the entries in this map |
2752 |
+ |
*/ |
2753 |
+ |
public Spliterator<Map.Entry<K,V>> entrySpliterator() { |
2754 |
+ |
return new EntryIterator<K,V>(this); |
2755 |
+ |
} |
2756 |
+ |
|
2757 |
+ |
/** |
2758 |
|
* Returns the hash code value for this {@link Map}, i.e., |
2759 |
|
* the sum of, for each key-value pair in the map, |
2760 |
|
* {@code key.hashCode() ^ value.hashCode()}. |
2763 |
|
*/ |
2764 |
|
public int hashCode() { |
2765 |
|
int h = 0; |
2766 |
< |
InternalIterator it = new InternalIterator(table); |
2767 |
< |
while (it.next != null) { |
2768 |
< |
h += it.nextKey.hashCode() ^ it.nextVal.hashCode(); |
2769 |
< |
it.advance(); |
2766 |
> |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
2767 |
> |
Object v; |
2768 |
> |
while ((v = it.advance()) != null) { |
2769 |
> |
h += it.nextKey.hashCode() ^ v.hashCode(); |
2770 |
|
} |
2771 |
|
return h; |
2772 |
|
} |
2783 |
|
* @return a string representation of this map |
2784 |
|
*/ |
2785 |
|
public String toString() { |
2786 |
< |
InternalIterator it = new InternalIterator(table); |
2786 |
> |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
2787 |
|
StringBuilder sb = new StringBuilder(); |
2788 |
|
sb.append('{'); |
2789 |
< |
if (it.next != null) { |
2789 |
> |
Object v; |
2790 |
> |
if ((v = it.advance()) != null) { |
2791 |
|
for (;;) { |
2792 |
< |
Object k = it.nextKey, v = it.nextVal; |
2792 |
> |
Object k = it.nextKey; |
2793 |
|
sb.append(k == this ? "(this Map)" : k); |
2794 |
|
sb.append('='); |
2795 |
|
sb.append(v == this ? "(this Map)" : v); |
2796 |
< |
it.advance(); |
1321 |
< |
if (it.next == null) |
2796 |
> |
if ((v = it.advance()) == null) |
2797 |
|
break; |
2798 |
|
sb.append(',').append(' '); |
2799 |
|
} |
2816 |
|
if (!(o instanceof Map)) |
2817 |
|
return false; |
2818 |
|
Map<?,?> m = (Map<?,?>) o; |
2819 |
< |
InternalIterator it = new InternalIterator(table); |
2820 |
< |
while (it.next != null) { |
2821 |
< |
Object val = it.nextVal; |
2819 |
> |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
2820 |
> |
Object val; |
2821 |
> |
while ((val = it.advance()) != null) { |
2822 |
|
Object v = m.get(it.nextKey); |
2823 |
|
if (v == null || (v != val && !v.equals(val))) |
2824 |
|
return false; |
1350 |
– |
it.advance(); |
2825 |
|
} |
2826 |
|
for (Map.Entry<?,?> e : m.entrySet()) { |
2827 |
|
Object mk, mv, v; |
2837 |
|
|
2838 |
|
/* ----------------Iterators -------------- */ |
2839 |
|
|
2840 |
< |
/** |
2841 |
< |
* Base class for key, value, and entry iterators. Adds a map |
2842 |
< |
* reference to InternalIterator to support Iterator.remove. |
2843 |
< |
*/ |
2844 |
< |
static abstract class ViewIterator<K,V> extends InternalIterator { |
1371 |
< |
final ConcurrentHashMapV8<K, V> map; |
1372 |
< |
ViewIterator(ConcurrentHashMapV8<K, V> map) { |
1373 |
< |
super(map.table); |
1374 |
< |
this.map = map; |
2840 |
> |
static final class KeyIterator<K,V> extends InternalIterator<K,V> |
2841 |
> |
implements Spliterator<K>, Enumeration<K> { |
2842 |
> |
KeyIterator(ConcurrentHashMapV8<K, V> map) { super(map); } |
2843 |
> |
KeyIterator(InternalIterator<K,V> it, boolean split) { |
2844 |
> |
super(it, split); |
2845 |
|
} |
2846 |
< |
|
2847 |
< |
public final void remove() { |
1378 |
< |
if (last == null) |
2846 |
> |
public KeyIterator<K,V> split() { |
2847 |
> |
if (last != null || (next != null && nextVal == null)) |
2848 |
|
throw new IllegalStateException(); |
2849 |
< |
map.remove(last.key); |
2850 |
< |
last = null; |
2849 |
> |
return new KeyIterator<K,V>(this, true); |
2850 |
> |
} |
2851 |
> |
public KeyIterator<K,V> clone() { |
2852 |
> |
if (last != null || (next != null && nextVal == null)) |
2853 |
> |
throw new IllegalStateException(); |
2854 |
> |
return new KeyIterator<K,V>(this, false); |
2855 |
|
} |
1383 |
– |
|
1384 |
– |
public final boolean hasNext() { return next != null; } |
1385 |
– |
public final boolean hasMoreElements() { return next != null; } |
1386 |
– |
} |
1387 |
– |
|
1388 |
– |
static final class KeyIterator<K,V> extends ViewIterator<K,V> |
1389 |
– |
implements Iterator<K>, Enumeration<K> { |
1390 |
– |
KeyIterator(ConcurrentHashMapV8<K, V> map) { super(map); } |
2856 |
|
|
2857 |
|
@SuppressWarnings("unchecked") |
2858 |
|
public final K next() { |
2859 |
< |
if (next == null) |
2859 |
> |
if (nextVal == null && advance() == null) |
2860 |
|
throw new NoSuchElementException(); |
2861 |
|
Object k = nextKey; |
2862 |
< |
advance(); |
2863 |
< |
return (K)k; |
2862 |
> |
nextVal = null; |
2863 |
> |
return (K) k; |
2864 |
|
} |
2865 |
|
|
2866 |
|
public final K nextElement() { return next(); } |
2867 |
|
} |
2868 |
|
|
2869 |
< |
static final class ValueIterator<K,V> extends ViewIterator<K,V> |
2870 |
< |
implements Iterator<V>, Enumeration<V> { |
2869 |
> |
static final class ValueIterator<K,V> extends InternalIterator<K,V> |
2870 |
> |
implements Spliterator<V>, Enumeration<V> { |
2871 |
|
ValueIterator(ConcurrentHashMapV8<K, V> map) { super(map); } |
2872 |
+ |
ValueIterator(InternalIterator<K,V> it, boolean split) { |
2873 |
+ |
super(it, split); |
2874 |
+ |
} |
2875 |
+ |
public ValueIterator<K,V> split() { |
2876 |
+ |
if (last != null || (next != null && nextVal == null)) |
2877 |
+ |
throw new IllegalStateException(); |
2878 |
+ |
return new ValueIterator<K,V>(this, true); |
2879 |
+ |
} |
2880 |
+ |
|
2881 |
+ |
public ValueIterator<K,V> clone() { |
2882 |
+ |
if (last != null || (next != null && nextVal == null)) |
2883 |
+ |
throw new IllegalStateException(); |
2884 |
+ |
return new ValueIterator<K,V>(this, false); |
2885 |
+ |
} |
2886 |
|
|
2887 |
|
@SuppressWarnings("unchecked") |
2888 |
|
public final V next() { |
2889 |
< |
if (next == null) |
2889 |
> |
Object v; |
2890 |
> |
if ((v = nextVal) == null && (v = advance()) == null) |
2891 |
|
throw new NoSuchElementException(); |
2892 |
< |
Object v = nextVal; |
2893 |
< |
advance(); |
1414 |
< |
return (V)v; |
2892 |
> |
nextVal = null; |
2893 |
> |
return (V) v; |
2894 |
|
} |
2895 |
|
|
2896 |
|
public final V nextElement() { return next(); } |
2897 |
|
} |
2898 |
|
|
2899 |
< |
static final class EntryIterator<K,V> extends ViewIterator<K,V> |
2900 |
< |
implements Iterator<Map.Entry<K,V>> { |
2899 |
> |
static final class EntryIterator<K,V> extends InternalIterator<K,V> |
2900 |
> |
implements Spliterator<Map.Entry<K,V>> { |
2901 |
|
EntryIterator(ConcurrentHashMapV8<K, V> map) { super(map); } |
2902 |
+ |
EntryIterator(InternalIterator<K,V> it, boolean split) { |
2903 |
+ |
super(it, split); |
2904 |
+ |
} |
2905 |
+ |
public EntryIterator<K,V> split() { |
2906 |
+ |
if (last != null || (next != null && nextVal == null)) |
2907 |
+ |
throw new IllegalStateException(); |
2908 |
+ |
return new EntryIterator<K,V>(this, true); |
2909 |
+ |
} |
2910 |
+ |
public EntryIterator<K,V> clone() { |
2911 |
+ |
if (last != null || (next != null && nextVal == null)) |
2912 |
+ |
throw new IllegalStateException(); |
2913 |
+ |
return new EntryIterator<K,V>(this, false); |
2914 |
+ |
} |
2915 |
|
|
2916 |
|
@SuppressWarnings("unchecked") |
2917 |
|
public final Map.Entry<K,V> next() { |
2918 |
< |
if (next == null) |
2918 |
> |
Object v; |
2919 |
> |
if ((v = nextVal) == null && (v = advance()) == null) |
2920 |
|
throw new NoSuchElementException(); |
2921 |
|
Object k = nextKey; |
2922 |
< |
Object v = nextVal; |
2923 |
< |
advance(); |
1431 |
< |
return new WriteThroughEntry<K,V>(map, (K)k, (V)v); |
2922 |
> |
nextVal = null; |
2923 |
> |
return new MapEntry<K,V>((K)k, (V)v, map); |
2924 |
|
} |
2925 |
|
} |
2926 |
|
|
2927 |
|
/** |
2928 |
< |
* Custom Entry class used by EntryIterator.next(), that relays |
1437 |
< |
* setValue changes to the underlying map. |
2928 |
> |
* Exported Entry for iterators |
2929 |
|
*/ |
2930 |
< |
static final class WriteThroughEntry<K,V> implements Map.Entry<K, V> { |
1440 |
< |
final ConcurrentHashMapV8<K, V> map; |
2930 |
> |
static final class MapEntry<K,V> implements Map.Entry<K, V> { |
2931 |
|
final K key; // non-null |
2932 |
|
V val; // non-null |
2933 |
< |
WriteThroughEntry(ConcurrentHashMapV8<K, V> map, K key, V val) { |
2934 |
< |
this.map = map; this.key = key; this.val = val; |
2933 |
> |
final ConcurrentHashMapV8<K, V> map; |
2934 |
> |
MapEntry(K key, V val, ConcurrentHashMapV8<K, V> map) { |
2935 |
> |
this.key = key; |
2936 |
> |
this.val = val; |
2937 |
> |
this.map = map; |
2938 |
|
} |
1446 |
– |
|
2939 |
|
public final K getKey() { return key; } |
2940 |
|
public final V getValue() { return val; } |
2941 |
|
public final int hashCode() { return key.hashCode() ^ val.hashCode(); } |
2952 |
|
|
2953 |
|
/** |
2954 |
|
* Sets our entry's value and writes through to the map. The |
2955 |
< |
* value to return is somewhat arbitrary here. Since a |
2956 |
< |
* WriteThroughEntry does not necessarily track asynchronous |
2957 |
< |
* changes, the most recent "previous" value could be |
2958 |
< |
* different from what we return (or could even have been |
2959 |
< |
* removed in which case the put will re-establish). We do not |
1468 |
< |
* and cannot guarantee more. |
2955 |
> |
* value to return is somewhat arbitrary here. Since a we do |
2956 |
> |
* not necessarily track asynchronous changes, the most recent |
2957 |
> |
* "previous" value could be different from what we return (or |
2958 |
> |
* could even have been removed in which case the put will |
2959 |
> |
* re-establish). We do not and cannot guarantee more. |
2960 |
|
*/ |
2961 |
|
public final V setValue(V value) { |
2962 |
|
if (value == null) throw new NullPointerException(); |
2969 |
|
|
2970 |
|
/* ----------------Views -------------- */ |
2971 |
|
|
2972 |
< |
/* |
2973 |
< |
* These currently just extend java.util.AbstractX classes, but |
1483 |
< |
* may need a new custom base to support partitioned traversal. |
2972 |
> |
/** |
2973 |
> |
* Base class for views. |
2974 |
|
*/ |
2975 |
< |
|
1486 |
< |
static final class KeySet<K,V> extends AbstractSet<K> { |
2975 |
> |
static abstract class MapView<K, V> { |
2976 |
|
final ConcurrentHashMapV8<K, V> map; |
2977 |
< |
KeySet(ConcurrentHashMapV8<K, V> map) { this.map = map; } |
1489 |
< |
|
2977 |
> |
MapView(ConcurrentHashMapV8<K, V> map) { this.map = map; } |
2978 |
|
public final int size() { return map.size(); } |
2979 |
|
public final boolean isEmpty() { return map.isEmpty(); } |
2980 |
|
public final void clear() { map.clear(); } |
2981 |
+ |
|
2982 |
+ |
// implementations below rely on concrete classes supplying these |
2983 |
+ |
abstract public Iterator<?> iterator(); |
2984 |
+ |
abstract public boolean contains(Object o); |
2985 |
+ |
abstract public boolean remove(Object o); |
2986 |
+ |
|
2987 |
+ |
private static final String oomeMsg = "Required array size too large"; |
2988 |
+ |
|
2989 |
+ |
public final Object[] toArray() { |
2990 |
+ |
long sz = map.longSize(); |
2991 |
+ |
if (sz > (long)(MAX_ARRAY_SIZE)) |
2992 |
+ |
throw new OutOfMemoryError(oomeMsg); |
2993 |
+ |
int n = (int)sz; |
2994 |
+ |
Object[] r = new Object[n]; |
2995 |
+ |
int i = 0; |
2996 |
+ |
Iterator<?> it = iterator(); |
2997 |
+ |
while (it.hasNext()) { |
2998 |
+ |
if (i == n) { |
2999 |
+ |
if (n >= MAX_ARRAY_SIZE) |
3000 |
+ |
throw new OutOfMemoryError(oomeMsg); |
3001 |
+ |
if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1) |
3002 |
+ |
n = MAX_ARRAY_SIZE; |
3003 |
+ |
else |
3004 |
+ |
n += (n >>> 1) + 1; |
3005 |
+ |
r = Arrays.copyOf(r, n); |
3006 |
+ |
} |
3007 |
+ |
r[i++] = it.next(); |
3008 |
+ |
} |
3009 |
+ |
return (i == n) ? r : Arrays.copyOf(r, i); |
3010 |
+ |
} |
3011 |
+ |
|
3012 |
+ |
@SuppressWarnings("unchecked") |
3013 |
+ |
public final <T> T[] toArray(T[] a) { |
3014 |
+ |
long sz = map.longSize(); |
3015 |
+ |
if (sz > (long)(MAX_ARRAY_SIZE)) |
3016 |
+ |
throw new OutOfMemoryError(oomeMsg); |
3017 |
+ |
int m = (int)sz; |
3018 |
+ |
T[] r = (a.length >= m) ? a : |
3019 |
+ |
(T[])java.lang.reflect.Array |
3020 |
+ |
.newInstance(a.getClass().getComponentType(), m); |
3021 |
+ |
int n = r.length; |
3022 |
+ |
int i = 0; |
3023 |
+ |
Iterator<?> it = iterator(); |
3024 |
+ |
while (it.hasNext()) { |
3025 |
+ |
if (i == n) { |
3026 |
+ |
if (n >= MAX_ARRAY_SIZE) |
3027 |
+ |
throw new OutOfMemoryError(oomeMsg); |
3028 |
+ |
if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1) |
3029 |
+ |
n = MAX_ARRAY_SIZE; |
3030 |
+ |
else |
3031 |
+ |
n += (n >>> 1) + 1; |
3032 |
+ |
r = Arrays.copyOf(r, n); |
3033 |
+ |
} |
3034 |
+ |
r[i++] = (T)it.next(); |
3035 |
+ |
} |
3036 |
+ |
if (a == r && i < n) { |
3037 |
+ |
r[i] = null; // null-terminate |
3038 |
+ |
return r; |
3039 |
+ |
} |
3040 |
+ |
return (i == n) ? r : Arrays.copyOf(r, i); |
3041 |
+ |
} |
3042 |
+ |
|
3043 |
+ |
public final int hashCode() { |
3044 |
+ |
int h = 0; |
3045 |
+ |
for (Iterator<?> it = iterator(); it.hasNext();) |
3046 |
+ |
h += it.next().hashCode(); |
3047 |
+ |
return h; |
3048 |
+ |
} |
3049 |
+ |
|
3050 |
+ |
public final String toString() { |
3051 |
+ |
StringBuilder sb = new StringBuilder(); |
3052 |
+ |
sb.append('['); |
3053 |
+ |
Iterator<?> it = iterator(); |
3054 |
+ |
if (it.hasNext()) { |
3055 |
+ |
for (;;) { |
3056 |
+ |
Object e = it.next(); |
3057 |
+ |
sb.append(e == this ? "(this Collection)" : e); |
3058 |
+ |
if (!it.hasNext()) |
3059 |
+ |
break; |
3060 |
+ |
sb.append(',').append(' '); |
3061 |
+ |
} |
3062 |
+ |
} |
3063 |
+ |
return sb.append(']').toString(); |
3064 |
+ |
} |
3065 |
+ |
|
3066 |
+ |
public final boolean containsAll(Collection<?> c) { |
3067 |
+ |
if (c != this) { |
3068 |
+ |
for (Iterator<?> it = c.iterator(); it.hasNext();) { |
3069 |
+ |
Object e = it.next(); |
3070 |
+ |
if (e == null || !contains(e)) |
3071 |
+ |
return false; |
3072 |
+ |
} |
3073 |
+ |
} |
3074 |
+ |
return true; |
3075 |
+ |
} |
3076 |
+ |
|
3077 |
+ |
public final boolean removeAll(Collection<?> c) { |
3078 |
+ |
boolean modified = false; |
3079 |
+ |
for (Iterator<?> it = iterator(); it.hasNext();) { |
3080 |
+ |
if (c.contains(it.next())) { |
3081 |
+ |
it.remove(); |
3082 |
+ |
modified = true; |
3083 |
+ |
} |
3084 |
+ |
} |
3085 |
+ |
return modified; |
3086 |
+ |
} |
3087 |
+ |
|
3088 |
+ |
public final boolean retainAll(Collection<?> c) { |
3089 |
+ |
boolean modified = false; |
3090 |
+ |
for (Iterator<?> it = iterator(); it.hasNext();) { |
3091 |
+ |
if (!c.contains(it.next())) { |
3092 |
+ |
it.remove(); |
3093 |
+ |
modified = true; |
3094 |
+ |
} |
3095 |
+ |
} |
3096 |
+ |
return modified; |
3097 |
+ |
} |
3098 |
+ |
|
3099 |
+ |
} |
3100 |
+ |
|
3101 |
+ |
static final class KeySet<K,V> extends MapView<K,V> implements Set<K> { |
3102 |
+ |
KeySet(ConcurrentHashMapV8<K, V> map) { super(map); } |
3103 |
|
public final boolean contains(Object o) { return map.containsKey(o); } |
3104 |
|
public final boolean remove(Object o) { return map.remove(o) != null; } |
3105 |
|
public final Iterator<K> iterator() { |
3106 |
|
return new KeyIterator<K,V>(map); |
3107 |
|
} |
3108 |
+ |
public final boolean add(K e) { |
3109 |
+ |
throw new UnsupportedOperationException(); |
3110 |
+ |
} |
3111 |
+ |
public final boolean addAll(Collection<? extends K> c) { |
3112 |
+ |
throw new UnsupportedOperationException(); |
3113 |
+ |
} |
3114 |
+ |
public boolean equals(Object o) { |
3115 |
+ |
Set<?> c; |
3116 |
+ |
return ((o instanceof Set) && |
3117 |
+ |
((c = (Set<?>)o) == this || |
3118 |
+ |
(containsAll(c) && c.containsAll(this)))); |
3119 |
+ |
} |
3120 |
|
} |
3121 |
|
|
3122 |
< |
static final class Values<K,V> extends AbstractCollection<V> { |
3123 |
< |
final ConcurrentHashMapV8<K, V> map; |
3124 |
< |
Values(ConcurrentHashMapV8<K, V> map) { this.map = map; } |
1503 |
< |
|
1504 |
< |
public final int size() { return map.size(); } |
1505 |
< |
public final boolean isEmpty() { return map.isEmpty(); } |
1506 |
< |
public final void clear() { map.clear(); } |
3122 |
> |
static final class Values<K,V> extends MapView<K,V> |
3123 |
> |
implements Collection<V> { |
3124 |
> |
Values(ConcurrentHashMapV8<K, V> map) { super(map); } |
3125 |
|
public final boolean contains(Object o) { return map.containsValue(o); } |
3126 |
+ |
public final boolean remove(Object o) { |
3127 |
+ |
if (o != null) { |
3128 |
+ |
Iterator<V> it = new ValueIterator<K,V>(map); |
3129 |
+ |
while (it.hasNext()) { |
3130 |
+ |
if (o.equals(it.next())) { |
3131 |
+ |
it.remove(); |
3132 |
+ |
return true; |
3133 |
+ |
} |
3134 |
+ |
} |
3135 |
+ |
} |
3136 |
+ |
return false; |
3137 |
+ |
} |
3138 |
|
public final Iterator<V> iterator() { |
3139 |
|
return new ValueIterator<K,V>(map); |
3140 |
|
} |
3141 |
< |
} |
3142 |
< |
|
1513 |
< |
static final class EntrySet<K,V> extends AbstractSet<Map.Entry<K,V>> { |
1514 |
< |
final ConcurrentHashMapV8<K, V> map; |
1515 |
< |
EntrySet(ConcurrentHashMapV8<K, V> map) { this.map = map; } |
1516 |
< |
|
1517 |
< |
public final int size() { return map.size(); } |
1518 |
< |
public final boolean isEmpty() { return map.isEmpty(); } |
1519 |
< |
public final void clear() { map.clear(); } |
1520 |
< |
public final Iterator<Map.Entry<K,V>> iterator() { |
1521 |
< |
return new EntryIterator<K,V>(map); |
3141 |
> |
public final boolean add(V e) { |
3142 |
> |
throw new UnsupportedOperationException(); |
3143 |
|
} |
3144 |
+ |
public final boolean addAll(Collection<? extends V> c) { |
3145 |
+ |
throw new UnsupportedOperationException(); |
3146 |
+ |
} |
3147 |
+ |
} |
3148 |
|
|
3149 |
+ |
static final class EntrySet<K,V> extends MapView<K,V> |
3150 |
+ |
implements Set<Map.Entry<K,V>> { |
3151 |
+ |
EntrySet(ConcurrentHashMapV8<K, V> map) { super(map); } |
3152 |
|
public final boolean contains(Object o) { |
3153 |
|
Object k, v, r; Map.Entry<?,?> e; |
3154 |
|
return ((o instanceof Map.Entry) && |
3157 |
|
(v = e.getValue()) != null && |
3158 |
|
(v == r || v.equals(r))); |
3159 |
|
} |
1532 |
– |
|
3160 |
|
public final boolean remove(Object o) { |
3161 |
|
Object k, v; Map.Entry<?,?> e; |
3162 |
|
return ((o instanceof Map.Entry) && |
3164 |
|
(v = e.getValue()) != null && |
3165 |
|
map.remove(k, v)); |
3166 |
|
} |
3167 |
+ |
public final Iterator<Map.Entry<K,V>> iterator() { |
3168 |
+ |
return new EntryIterator<K,V>(map); |
3169 |
+ |
} |
3170 |
+ |
public final boolean add(Entry<K,V> e) { |
3171 |
+ |
throw new UnsupportedOperationException(); |
3172 |
+ |
} |
3173 |
+ |
public final boolean addAll(Collection<? extends Entry<K,V>> c) { |
3174 |
+ |
throw new UnsupportedOperationException(); |
3175 |
+ |
} |
3176 |
+ |
public boolean equals(Object o) { |
3177 |
+ |
Set<?> c; |
3178 |
+ |
return ((o instanceof Set) && |
3179 |
+ |
((c = (Set<?>)o) == this || |
3180 |
+ |
(containsAll(c) && c.containsAll(this)))); |
3181 |
+ |
} |
3182 |
|
} |
3183 |
|
|
3184 |
|
/* ---------------- Serialization Support -------------- */ |
3209 |
|
segments = (Segment<K,V>[]) |
3210 |
|
new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL]; |
3211 |
|
for (int i = 0; i < segments.length; ++i) |
3212 |
< |
segments[i] = new Segment<K,V>(DEFAULT_LOAD_FACTOR); |
3212 |
> |
segments[i] = new Segment<K,V>(LOAD_FACTOR); |
3213 |
|
} |
3214 |
|
s.defaultWriteObject(); |
3215 |
< |
InternalIterator it = new InternalIterator(table); |
3216 |
< |
while (it.next != null) { |
3215 |
> |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
3216 |
> |
Object v; |
3217 |
> |
while ((v = it.advance()) != null) { |
3218 |
|
s.writeObject(it.nextKey); |
3219 |
< |
s.writeObject(it.nextVal); |
1577 |
< |
it.advance(); |
3219 |
> |
s.writeObject(v); |
3220 |
|
} |
3221 |
|
s.writeObject(null); |
3222 |
|
s.writeObject(null); |
3232 |
|
throws java.io.IOException, ClassNotFoundException { |
3233 |
|
s.defaultReadObject(); |
3234 |
|
this.segments = null; // unneeded |
3235 |
< |
// initalize transient final fields |
3235 |
> |
// initialize transient final field |
3236 |
|
UNSAFE.putObjectVolatile(this, counterOffset, new LongAdder()); |
1595 |
– |
UNSAFE.putFloatVolatile(this, loadFactorOffset, DEFAULT_LOAD_FACTOR); |
1596 |
– |
this.targetCapacity = DEFAULT_CAPACITY; |
3237 |
|
|
3238 |
|
// Create all nodes, then place in table once size is known |
3239 |
|
long size = 0L; |
3242 |
|
K k = (K) s.readObject(); |
3243 |
|
V v = (V) s.readObject(); |
3244 |
|
if (k != null && v != null) { |
3245 |
< |
p = new Node(spread(k.hashCode()), k, v, p); |
3245 |
> |
int h = spread(k.hashCode()); |
3246 |
> |
p = new Node(h, k, v, p); |
3247 |
|
++size; |
3248 |
|
} |
3249 |
|
else |
3251 |
|
} |
3252 |
|
if (p != null) { |
3253 |
|
boolean init = false; |
3254 |
< |
if (resizing == 0 && |
3255 |
< |
UNSAFE.compareAndSwapInt(this, resizingOffset, 0, 1)) { |
3254 |
> |
int n; |
3255 |
> |
if (size >= (long)(MAXIMUM_CAPACITY >>> 1)) |
3256 |
> |
n = MAXIMUM_CAPACITY; |
3257 |
> |
else { |
3258 |
> |
int sz = (int)size; |
3259 |
> |
n = tableSizeFor(sz + (sz >>> 1) + 1); |
3260 |
> |
} |
3261 |
> |
int sc = sizeCtl; |
3262 |
> |
boolean collide = false; |
3263 |
> |
if (n > sc && |
3264 |
> |
UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) { |
3265 |
|
try { |
3266 |
|
if (table == null) { |
3267 |
|
init = true; |
1618 |
– |
int n; |
1619 |
– |
if (size >= (long)(MAXIMUM_CAPACITY >>> 1)) |
1620 |
– |
n = MAXIMUM_CAPACITY; |
1621 |
– |
else { |
1622 |
– |
int sz = (int)size; |
1623 |
– |
n = tableSizeFor(sz + (sz >>> 1)); |
1624 |
– |
} |
1625 |
– |
threshold = (n - (n >>> 2)) - THRESHOLD_OFFSET; |
3268 |
|
Node[] tab = new Node[n]; |
3269 |
|
int mask = n - 1; |
3270 |
|
while (p != null) { |
3271 |
|
int j = p.hash & mask; |
3272 |
|
Node next = p.next; |
3273 |
< |
p.next = tabAt(tab, j); |
3273 |
> |
Node q = p.next = tabAt(tab, j); |
3274 |
|
setTabAt(tab, j, p); |
3275 |
+ |
if (!collide && q != null && q.hash == p.hash) |
3276 |
+ |
collide = true; |
3277 |
|
p = next; |
3278 |
|
} |
3279 |
|
table = tab; |
3280 |
|
counter.add(size); |
3281 |
+ |
sc = n - (n >>> 2); |
3282 |
|
} |
3283 |
|
} finally { |
3284 |
< |
resizing = 0; |
3284 |
> |
sizeCtl = sc; |
3285 |
> |
} |
3286 |
> |
if (collide) { // rescan and convert to TreeBins |
3287 |
> |
Node[] tab = table; |
3288 |
> |
for (int i = 0; i < tab.length; ++i) { |
3289 |
> |
int c = 0; |
3290 |
> |
for (Node e = tabAt(tab, i); e != null; e = e.next) { |
3291 |
> |
if (++c > TREE_THRESHOLD && |
3292 |
> |
(e.key instanceof Comparable)) { |
3293 |
> |
replaceWithTreeBin(tab, i, e.key); |
3294 |
> |
break; |
3295 |
> |
} |
3296 |
> |
} |
3297 |
> |
} |
3298 |
|
} |
3299 |
|
} |
3300 |
|
if (!init) { // Can only happen if unsafely published. |
3301 |
|
while (p != null) { |
3302 |
< |
internalPut(p.key, p.val, true); |
3302 |
> |
internalPut(p.key, p.val); |
3303 |
|
p = p.next; |
3304 |
|
} |
3305 |
|
} |
3309 |
|
// Unsafe mechanics |
3310 |
|
private static final sun.misc.Unsafe UNSAFE; |
3311 |
|
private static final long counterOffset; |
3312 |
< |
private static final long loadFactorOffset; |
1655 |
< |
private static final long resizingOffset; |
3312 |
> |
private static final long sizeCtlOffset; |
3313 |
|
private static final long ABASE; |
3314 |
|
private static final int ASHIFT; |
3315 |
|
|
3320 |
|
Class<?> k = ConcurrentHashMapV8.class; |
3321 |
|
counterOffset = UNSAFE.objectFieldOffset |
3322 |
|
(k.getDeclaredField("counter")); |
3323 |
< |
loadFactorOffset = UNSAFE.objectFieldOffset |
3324 |
< |
(k.getDeclaredField("loadFactor")); |
1668 |
< |
resizingOffset = UNSAFE.objectFieldOffset |
1669 |
< |
(k.getDeclaredField("resizing")); |
3323 |
> |
sizeCtlOffset = UNSAFE.objectFieldOffset |
3324 |
> |
(k.getDeclaredField("sizeCtl")); |
3325 |
|
Class<?> sc = Node[].class; |
3326 |
|
ABASE = UNSAFE.arrayBaseOffset(sc); |
3327 |
|
ss = UNSAFE.arrayIndexScale(sc); |