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1.1 |
/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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package jsr166e; |
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import jsr166e.LongAdder; |
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1.24 |
import java.util.Arrays; |
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1.1 |
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.AbstractMap; |
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import java.util.AbstractSet; |
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import java.util.AbstractCollection; |
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import java.util.Hashtable; |
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import java.util.HashMap; |
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import java.util.Iterator; |
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import java.util.Enumeration; |
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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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1.37 |
import java.util.concurrent.ThreadLocalRandom; |
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1.24 |
import java.util.concurrent.locks.LockSupport; |
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1.38 |
import java.util.concurrent.locks.AbstractQueuedSynchronizer; |
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1.1 |
import java.io.Serializable; |
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/** |
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* A hash table supporting full concurrency of retrievals and |
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* high expected concurrency for updates. This class obeys the |
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* same functional specification as {@link java.util.Hashtable}, and |
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* includes versions of methods corresponding to each method of |
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* {@code Hashtable}. However, even though all operations are |
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* thread-safe, retrieval operations do <em>not</em> entail locking, |
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* and there is <em>not</em> any support for locking the entire table |
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* in a way that prevents all access. This class is fully |
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* interoperable with {@code Hashtable} in programs that rely on its |
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* thread safety but not on its synchronization details. |
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* |
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* <p> Retrieval operations (including {@code get}) generally do not |
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* block, so may overlap with update operations (including {@code put} |
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* and {@code remove}). Retrievals reflect the results of the most |
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* recently <em>completed</em> update operations holding upon their |
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* onset. For aggregate operations such as {@code putAll} and {@code |
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* clear}, concurrent retrievals may reflect insertion or removal of |
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* only some entries. Similarly, Iterators and Enumerations return |
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* elements reflecting the state of the hash table at some point at or |
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* since the creation of the iterator/enumeration. They do |
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* <em>not</em> throw {@link ConcurrentModificationException}. |
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* However, iterators are designed to be used by only one thread at a |
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* time. Bear in mind that the results of aggregate status methods |
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* including {@code size}, {@code isEmpty}, and {@code containsValue} |
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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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1.16 |
* or estimation purposes, but not for program control. |
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1.1 |
* |
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1.16 |
* <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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1.24 |
* 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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1.16 |
* 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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jsr166 |
1.31 |
* {@code hashCode()} is a sure way to slow down performance of any |
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1.16 |
* hash table. |
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1.1 |
* |
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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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* interfaces. |
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* |
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* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class |
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* does <em>not</em> allow {@code null} to be used as a key or value. |
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* |
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* <p>This class is a member of the |
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* <a href="{@docRoot}/../technotes/guides/collections/index.html"> |
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* Java Collections Framework</a>. |
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* |
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* <p><em>jsr166e note: This class is a candidate replacement for |
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* java.util.concurrent.ConcurrentHashMap.<em> |
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* |
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jsr166 |
1.22 |
* @since 1.5 |
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1.1 |
* @author Doug Lea |
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* @param <K> the type of keys maintained by this map |
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* @param <V> the type of mapped values |
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*/ |
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public class ConcurrentHashMapV8<K, V> |
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implements ConcurrentMap<K, V>, Serializable { |
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private static final long serialVersionUID = 7249069246763182397L; |
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/** |
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1.27 |
* 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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dl |
1.1 |
*/ |
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public static interface MappingFunction<K, V> { |
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/** |
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jsr166 |
1.43 |
* Returns a value for the given key, or null if there is no mapping. |
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1.1 |
* |
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* @param key the (non-null) key |
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1.41 |
* @return a value for the key, or null if none |
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1.1 |
*/ |
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V map(K key); |
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} |
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dl |
1.27 |
/** |
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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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dl |
1.41 |
* @return a value for the key, or null if none |
129 |
dl |
1.27 |
*/ |
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V remap(K key, V value); |
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} |
132 |
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dl |
1.41 |
/** |
134 |
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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, |
148 |
jsr166 |
1.44 |
* and then joins these subtasks. Variants of this style can also |
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* be used in completion-based designs. |
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dl |
1.41 |
* |
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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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* // ... |
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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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* } |
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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 |
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* the elements of the returned Spliterator, but the two |
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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 |
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* produced by the returned Spliterator is not guaranteed, and |
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* may be zero (i.e., with {@code hasNext()} reporting {@code |
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* false}) if this Spliterator cannot be further split. |
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* |
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* @return a Spliterator covering approximately half of the |
193 |
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* elements |
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* @throws IllegalStateException if this Spliterator has |
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* already commenced traversing elements. |
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*/ |
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Spliterator<T> split(); |
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/** |
200 |
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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 |
203 |
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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. |
206 |
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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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dl |
1.1 |
/* |
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* Overview: |
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* |
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* The primary design goal of this hash table is to maintain |
216 |
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* concurrent readability (typically method get(), but also |
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* iterators and related methods) while minimizing update |
218 |
dl |
1.24 |
* contention. Secondary goals are to keep space consumption about |
219 |
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* the same or better than java.util.HashMap, and to support high |
220 |
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* initial insertion rates on an empty table by many threads. |
221 |
dl |
1.1 |
* |
222 |
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* Each key-value mapping is held in a Node. Because Node fields |
223 |
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* can contain special values, they are defined using plain Object |
224 |
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* types. Similarly in turn, all internal methods that use them |
225 |
dl |
1.14 |
* work off Object types. And similarly, so do the internal |
226 |
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* methods of auxiliary iterator and view classes. All public |
227 |
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* generic typed methods relay in/out of these internal methods, |
228 |
dl |
1.27 |
* supplying null-checks and casts as needed. This also allows |
229 |
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* many of the public methods to be factored into a smaller number |
230 |
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* of internal methods (although sadly not so for the five |
231 |
dl |
1.38 |
* variants of put-related operations). The validation-based |
232 |
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* approach explained below leads to a lot of code sprawl because |
233 |
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* retry-control precludes factoring into smaller methods. |
234 |
dl |
1.1 |
* |
235 |
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* The table is lazily initialized to a power-of-two size upon the |
236 |
dl |
1.38 |
* 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 |
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* CASes. Because there is no other way to arrange this without |
240 |
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* adding further indirections, we use intrinsics |
241 |
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* (sun.misc.Unsafe) operations. The lists of nodes within bins |
242 |
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* 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 |
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* checking key equality. |
245 |
dl |
1.24 |
* |
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 |
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* constraints. As explained further below, these top bits are |
249 |
dl |
1.27 |
* used as follows: |
250 |
dl |
1.24 |
* 00 - Normal |
251 |
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* 01 - Locked |
252 |
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* 11 - Locked and may have a thread waiting for lock |
253 |
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* 10 - Node is a forwarding node |
254 |
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* |
255 |
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* The lower 30 bits of each Node's hash field contain a |
256 |
dl |
1.38 |
* transformation of the key's hash code, except for forwarding |
257 |
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* nodes, for which the lower bits are zero (and so always have |
258 |
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* hash field == MOVED). |
259 |
dl |
1.14 |
* |
260 |
dl |
1.27 |
* Insertion (via put or its variants) of the first node in an |
261 |
dl |
1.14 |
* empty bin is performed by just CASing it to the bin. This is |
262 |
dl |
1.38 |
* by far the most common case for put operations under most |
263 |
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* key/hash distributions. Other update operations (insert, |
264 |
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* delete, and replace) require locks. We do not want to waste |
265 |
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* the space required to associate a distinct lock object with |
266 |
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* each bin, so instead use the first node of a bin list itself as |
267 |
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* a lock. Blocking support for these locks relies on the builtin |
268 |
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* "synchronized" monitors. However, we also need a tryLock |
269 |
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* construction, so we overlay these by using bits of the Node |
270 |
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* hash field for lock control (see above), and so normally use |
271 |
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* builtin monitors only for blocking and signalling using |
272 |
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* wait/notifyAll constructions. See Node.tryAwaitLock. |
273 |
dl |
1.24 |
* |
274 |
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* Using the first node of a list as a lock does not by itself |
275 |
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* suffice though: When a node is locked, any update must first |
276 |
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* validate that it is still the first node after locking it, and |
277 |
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* retry if not. Because new nodes are always appended to lists, |
278 |
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* once a node is first in a bin, it remains first until deleted |
279 |
dl |
1.27 |
* or the bin becomes invalidated (upon resizing). However, |
280 |
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* operations that only conditionally update may inspect nodes |
281 |
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* until the point of update. This is a converse of sorts to the |
282 |
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* lazy locking technique described by Herlihy & Shavit. |
283 |
dl |
1.14 |
* |
284 |
dl |
1.24 |
* The main disadvantage of per-bin locks is that other update |
285 |
dl |
1.14 |
* operations on other nodes in a bin list protected by the same |
286 |
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* lock can stall, for example when user equals() or mapping |
287 |
dl |
1.38 |
* functions take a long time. However, statistically, under |
288 |
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* random hash codes, this is not a common problem. Ideally, the |
289 |
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* frequency of nodes in bins follows a Poisson distribution |
290 |
dl |
1.14 |
* (http://en.wikipedia.org/wiki/Poisson_distribution) with a |
291 |
dl |
1.16 |
* parameter of about 0.5 on average, given the resizing threshold |
292 |
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* of 0.75, although with a large variance because of resizing |
293 |
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* granularity. Ignoring variance, the expected occurrences of |
294 |
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* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The |
295 |
dl |
1.38 |
* first values are: |
296 |
dl |
1.16 |
* |
297 |
dl |
1.38 |
* 0: 0.60653066 |
298 |
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* 1: 0.30326533 |
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* 2: 0.07581633 |
300 |
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* 3: 0.01263606 |
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* 4: 0.00157952 |
302 |
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* 5: 0.00015795 |
303 |
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* 6: 0.00001316 |
304 |
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* 7: 0.00000094 |
305 |
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* 8: 0.00000006 |
306 |
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* more: less than 1 in ten million |
307 |
dl |
1.16 |
* |
308 |
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* Lock contention probability for two threads accessing distinct |
309 |
dl |
1.38 |
* elements is roughly 1 / (8 * #elements) under random hashes. |
310 |
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* |
311 |
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* Actual hash code distributions encountered in practice |
312 |
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* sometimes deviate significantly from uniform randomness. This |
313 |
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* includes the case when N > (1<<30), so some keys MUST collide. |
314 |
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* Similarly for dumb or hostile usages in which multiple keys are |
315 |
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* designed to have identical hash codes. Also, although we guard |
316 |
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* against the worst effects of this (see method spread), sets of |
317 |
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* hashes may differ only in bits that do not impact their bin |
318 |
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* index for a given power-of-two mask. So we use a secondary |
319 |
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* strategy that applies when the number of nodes in a bin exceeds |
320 |
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* a threshold, and at least one of the keys implements |
321 |
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* Comparable. These TreeBins use a balanced tree to hold nodes |
322 |
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* (a specialized form of red-black trees), bounding search time |
323 |
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* to O(log N). Each search step in a TreeBin is around twice as |
324 |
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* slow as in a regular list, but given that N cannot exceed |
325 |
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* (1<<64) (before running out of addresses) this bounds search |
326 |
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* steps, lock hold times, etc, to reasonable constants (roughly |
327 |
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* 100 nodes inspected per operation worst case) so long as keys |
328 |
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* are Comparable (which is very common -- String, Long, etc). |
329 |
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* TreeBin nodes (TreeNodes) also maintain the same "next" |
330 |
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* traversal pointers as regular nodes, so can be traversed in |
331 |
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* iterators in the same way. |
332 |
dl |
1.1 |
* |
333 |
dl |
1.38 |
* The table is resized when occupancy exceeds a percentage |
334 |
dl |
1.24 |
* threshold (nominally, 0.75, but see below). Only a single |
335 |
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* thread performs the resize (using field "sizeCtl", to arrange |
336 |
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* exclusion), but the table otherwise remains usable for reads |
337 |
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|
* 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 |
dl |
1.38 |
* 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 |
dl |
1.24 |
* mechanics trigger only when necessary. |
371 |
dl |
1.14 |
* |
372 |
dl |
1.24 |
* The traversal scheme also applies to partial traversals of |
373 |
dl |
1.14 |
* ranges of bins (via an alternate InternalIterator constructor) |
374 |
dl |
1.41 |
* 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 |
dl |
1.14 |
* |
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 |
dl |
1.24 |
* These cases attempt to override the initial capacity settings, |
383 |
|
|
* but harmlessly fail to take effect in cases of races. |
384 |
dl |
1.1 |
* |
385 |
|
|
* The element count is maintained using a LongAdder, which avoids |
386 |
|
|
* contention on updates but can encounter cache thrashing if read |
387 |
dl |
1.14 |
* too frequently during concurrent access. To avoid reading so |
388 |
dl |
1.27 |
* 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 |
dl |
1.14 |
* |
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 |
dl |
1.24 |
* 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 |
dl |
1.1 |
*/ |
409 |
|
|
|
410 |
|
|
/* ---------------- Constants -------------- */ |
411 |
|
|
|
412 |
|
|
/** |
413 |
dl |
1.16 |
* The largest possible table capacity. This value must be |
414 |
|
|
* exactly 1<<30 to stay within Java array allocation and indexing |
415 |
dl |
1.24 |
* 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 |
dl |
1.1 |
*/ |
419 |
dl |
1.14 |
private static final int MAXIMUM_CAPACITY = 1 << 30; |
420 |
dl |
1.1 |
|
421 |
|
|
/** |
422 |
dl |
1.14 |
* The default initial table capacity. Must be a power of 2 |
423 |
|
|
* (i.e., at least 1) and at most MAXIMUM_CAPACITY. |
424 |
dl |
1.1 |
*/ |
425 |
dl |
1.14 |
private static final int DEFAULT_CAPACITY = 16; |
426 |
dl |
1.1 |
|
427 |
|
|
/** |
428 |
dl |
1.24 |
* The largest possible (non-power of two) array size. |
429 |
|
|
* Needed by toArray and related methods. |
430 |
|
|
*/ |
431 |
|
|
static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; |
432 |
|
|
|
433 |
|
|
/** |
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 |
dl |
1.16 |
* The load factor for this table. Overrides of this value in |
441 |
|
|
* constructors affect only the initial table capacity. The |
442 |
dl |
1.24 |
* 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 |
dl |
1.1 |
*/ |
446 |
dl |
1.16 |
private static final float LOAD_FACTOR = 0.75f; |
447 |
dl |
1.1 |
|
448 |
|
|
/** |
449 |
dl |
1.24 |
* 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 |
|
|
private static final int TRANSFER_BUFFER_SIZE = 32; |
454 |
|
|
|
455 |
dl |
1.38 |
/** |
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 TREE_THRESHOLD = 8; |
461 |
|
|
|
462 |
dl |
1.24 |
/* |
463 |
|
|
* Encodings for special uses of Node hash fields. See above for |
464 |
|
|
* explanation. |
465 |
dl |
1.1 |
*/ |
466 |
jsr166 |
1.35 |
static final int MOVED = 0x80000000; // hash field for forwarding nodes |
467 |
dl |
1.24 |
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 |
|
|
|
473 |
|
|
/** |
474 |
|
|
* The array of bins. Lazily initialized upon first insertion. |
475 |
|
|
* Size is always a power of two. Accessed directly by iterators. |
476 |
|
|
*/ |
477 |
|
|
transient volatile Node[] table; |
478 |
dl |
1.14 |
|
479 |
dl |
1.16 |
/** |
480 |
dl |
1.24 |
* The counter maintaining number of elements. |
481 |
dl |
1.16 |
*/ |
482 |
dl |
1.24 |
private transient final LongAdder counter; |
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; |
495 |
|
|
private transient Values<K,V> values; |
496 |
|
|
private transient EntrySet<K,V> entrySet; |
497 |
|
|
|
498 |
|
|
/** For serialization compatibility. Null unless serialized; see below */ |
499 |
|
|
private Segment<K,V>[] segments; |
500 |
dl |
1.16 |
|
501 |
dl |
1.38 |
/* ---------------- Table element access -------------- */ |
502 |
|
|
|
503 |
|
|
/* |
504 |
|
|
* Volatile access methods are used for table elements as well as |
505 |
|
|
* elements of in-progress next table while resizing. Uses are |
506 |
|
|
* null checked by callers, and implicitly bounds-checked, relying |
507 |
|
|
* on the invariants that tab arrays have non-zero size, and all |
508 |
|
|
* indices are masked with (tab.length - 1) which is never |
509 |
|
|
* negative and always less than length. Note that, to be correct |
510 |
|
|
* wrt arbitrary concurrency errors by users, bounds checks must |
511 |
|
|
* operate on local variables, which accounts for some odd-looking |
512 |
|
|
* inline assignments below. |
513 |
|
|
*/ |
514 |
|
|
|
515 |
|
|
static final Node tabAt(Node[] tab, int i) { // used by InternalIterator |
516 |
|
|
return (Node)UNSAFE.getObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE); |
517 |
|
|
} |
518 |
|
|
|
519 |
|
|
private static final boolean casTabAt(Node[] tab, int i, Node c, Node v) { |
520 |
|
|
return UNSAFE.compareAndSwapObject(tab, ((long)i<<ASHIFT)+ABASE, c, v); |
521 |
|
|
} |
522 |
|
|
|
523 |
|
|
private static final void setTabAt(Node[] tab, int i, Node v) { |
524 |
|
|
UNSAFE.putObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE, v); |
525 |
|
|
} |
526 |
|
|
|
527 |
dl |
1.14 |
/* ---------------- Nodes -------------- */ |
528 |
dl |
1.1 |
|
529 |
|
|
/** |
530 |
dl |
1.14 |
* Key-value entry. Note that this is never exported out as a |
531 |
dl |
1.41 |
* 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 |
dl |
1.1 |
*/ |
539 |
dl |
1.38 |
static class Node { |
540 |
dl |
1.24 |
volatile int hash; |
541 |
dl |
1.14 |
final Object key; |
542 |
|
|
volatile Object val; |
543 |
|
|
volatile Node next; |
544 |
|
|
|
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 |
dl |
1.24 |
/** CompareAndSet the hash field */ |
553 |
|
|
final boolean casHash(int cmp, int val) { |
554 |
|
|
return UNSAFE.compareAndSwapInt(this, hashOffset, cmp, val); |
555 |
|
|
} |
556 |
dl |
1.1 |
|
557 |
dl |
1.24 |
/** The number of spins before blocking for a lock */ |
558 |
|
|
static final int MAX_SPINS = |
559 |
|
|
Runtime.getRuntime().availableProcessors() > 1 ? 64 : 1; |
560 |
dl |
1.1 |
|
561 |
dl |
1.24 |
/** |
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 |
dl |
1.37 |
int r = ThreadLocalRandom.current().nextInt(); // randomize spins |
577 |
dl |
1.24 |
int spins = MAX_SPINS, h; |
578 |
|
|
while (tabAt(tab, i) == this && ((h = hash) & LOCKED) != 0) { |
579 |
|
|
if (spins >= 0) { |
580 |
dl |
1.37 |
r ^= r << 1; r ^= r >>> 3; r ^= r << 10; // xorshift |
581 |
|
|
if (r >= 0 && --spins == 0) |
582 |
|
|
Thread.yield(); // yield before block |
583 |
dl |
1.24 |
} |
584 |
|
|
else if (casHash(h, h | WAITING)) { |
585 |
jsr166 |
1.26 |
synchronized (this) { |
586 |
dl |
1.24 |
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 |
|
|
} |
600 |
|
|
} |
601 |
|
|
} |
602 |
dl |
1.1 |
|
603 |
dl |
1.24 |
// Unsafe mechanics for casHash |
604 |
|
|
private static final sun.misc.Unsafe UNSAFE; |
605 |
|
|
private static final long hashOffset; |
606 |
dl |
1.1 |
|
607 |
dl |
1.24 |
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 |
dl |
1.1 |
|
619 |
dl |
1.38 |
/* ---------------- TreeBins -------------- */ |
620 |
|
|
|
621 |
|
|
/** |
622 |
|
|
* Nodes for use in TreeBins |
623 |
|
|
*/ |
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 |
dl |
1.1 |
|
637 |
dl |
1.38 |
/** |
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 |
dl |
1.41 |
* 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 |
dl |
1.38 |
* |
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 |
dl |
1.1 |
*/ |
680 |
dl |
1.38 |
static final class TreeBin extends AbstractQueuedSynchronizer { |
681 |
|
|
private static final long serialVersionUID = 2249069246763182397L; |
682 |
dl |
1.41 |
transient TreeNode root; // root of tree |
683 |
|
|
transient TreeNode first; // head of next-pointer list |
684 |
dl |
1.1 |
|
685 |
dl |
1.38 |
/* 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 |
dl |
1.41 |
/** 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 |
dl |
1.38 |
/** |
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 |
dl |
1.41 |
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 |
jsr166 |
1.42 |
dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName()); |
763 |
dl |
1.41 |
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 |
dl |
1.38 |
else |
775 |
dl |
1.41 |
dir = (h < ph) ? -1 : 1; |
776 |
|
|
p = (dir > 0) ? p.right : p.left; |
777 |
dl |
1.38 |
} |
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 |
dl |
1.41 |
TreeNode pp = root, p = null; |
816 |
dl |
1.38 |
int dir = 0; |
817 |
dl |
1.41 |
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 |
dl |
1.38 |
return p; |
823 |
dl |
1.41 |
if (c != (pc = pk.getClass()) || |
824 |
|
|
!(k instanceof Comparable) || |
825 |
|
|
(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) { |
826 |
jsr166 |
1.42 |
dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName()); |
827 |
dl |
1.41 |
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 |
dl |
1.38 |
} |
837 |
|
|
} |
838 |
dl |
1.41 |
else |
839 |
|
|
dir = (h < ph) ? -1 : 1; |
840 |
|
|
pp = (dir > 0) ? p.right : p.left; |
841 |
dl |
1.38 |
} |
842 |
dl |
1.41 |
|
843 |
dl |
1.38 |
TreeNode f = first; |
844 |
dl |
1.41 |
TreeNode x = first = new TreeNode(h, k, v, f, p); |
845 |
dl |
1.38 |
if (p == null) |
846 |
dl |
1.41 |
root = x; |
847 |
|
|
else { // attach and rebalance; adapted from CLR |
848 |
|
|
TreeNode xp, xpp; |
849 |
|
|
if (f != null) |
850 |
|
|
f.prev = x; |
851 |
dl |
1.38 |
if (dir <= 0) |
852 |
dl |
1.41 |
p.left = x; |
853 |
dl |
1.38 |
else |
854 |
dl |
1.41 |
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 |
|
|
} |
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 |
|
|
} |
901 |
|
|
} |
902 |
|
|
} |
903 |
|
|
} |
904 |
|
|
TreeNode r = root; |
905 |
|
|
if (r != null && r.red) |
906 |
|
|
r.red = false; |
907 |
dl |
1.38 |
} |
908 |
|
|
return null; |
909 |
|
|
} |
910 |
dl |
1.1 |
|
911 |
dl |
1.38 |
/** |
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 |
dl |
1.41 |
TreeNode s = pr, sl; |
933 |
|
|
while ((sl = s.left) != null) // find successor |
934 |
|
|
s = sl; |
935 |
dl |
1.38 |
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 |
dl |
1.41 |
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 |
dl |
1.38 |
} |
994 |
dl |
1.41 |
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 |
dl |
1.38 |
} |
1002 |
dl |
1.41 |
if (sib == null) |
1003 |
dl |
1.38 |
x = xp; |
1004 |
|
|
else { |
1005 |
dl |
1.41 |
TreeNode sl = sib.left, sr = sib.right; |
1006 |
|
|
if ((sr == null || !sr.red) && |
1007 |
|
|
(sl == null || !sl.red)) { |
1008 |
dl |
1.38 |
sib.red = true; |
1009 |
dl |
1.41 |
x = xp; |
1010 |
dl |
1.38 |
} |
1011 |
dl |
1.41 |
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 |
jsr166 |
1.42 |
sib.red = (xp == null) ? false : xp.red; |
1021 |
dl |
1.41 |
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 |
dl |
1.38 |
} |
1030 |
|
|
} |
1031 |
|
|
} |
1032 |
dl |
1.41 |
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 |
dl |
1.38 |
x = xp; |
1042 |
|
|
else { |
1043 |
dl |
1.41 |
TreeNode sl = sib.left, sr = sib.right; |
1044 |
|
|
if ((sl == null || !sl.red) && |
1045 |
|
|
(sr == null || !sr.red)) { |
1046 |
dl |
1.38 |
sib.red = true; |
1047 |
dl |
1.41 |
x = xp; |
1048 |
dl |
1.38 |
} |
1049 |
dl |
1.41 |
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 |
jsr166 |
1.42 |
sib.red = (xp == null) ? false : xp.red; |
1059 |
dl |
1.41 |
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 |
dl |
1.38 |
} |
1068 |
|
|
} |
1069 |
|
|
} |
1070 |
|
|
} |
1071 |
|
|
} |
1072 |
dl |
1.41 |
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 |
dl |
1.38 |
} |
1080 |
dl |
1.1 |
} |
1081 |
|
|
|
1082 |
dl |
1.38 |
/* ---------------- Collision reduction methods -------------- */ |
1083 |
dl |
1.14 |
|
1084 |
|
|
/** |
1085 |
dl |
1.38 |
* 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 |
jsr166 |
1.40 |
* are already reasonably distributed across bits (so don't benefit |
1094 |
dl |
1.38 |
* from spreading), and because we use trees to handle large sets |
1095 |
|
|
* of collisions in bins, we don't need excessively high quality. |
1096 |
dl |
1.14 |
*/ |
1097 |
|
|
private static final int spread(int h) { |
1098 |
dl |
1.38 |
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 |
dl |
1.14 |
} |
1116 |
dl |
1.1 |
|
1117 |
dl |
1.38 |
/* ---------------- Internal access and update methods -------------- */ |
1118 |
|
|
|
1119 |
dl |
1.14 |
/** Implementation for get and containsKey */ |
1120 |
jsr166 |
1.4 |
private final Object internalGet(Object k) { |
1121 |
dl |
1.1 |
int h = spread(k.hashCode()); |
1122 |
dl |
1.14 |
retry: for (Node[] tab = table; tab != null;) { |
1123 |
dl |
1.38 |
Node e, p; Object ek, ev; int eh; // locals to read fields once |
1124 |
dl |
1.14 |
for (e = tabAt(tab, (tab.length - 1) & h); e != null; e = e.next) { |
1125 |
dl |
1.24 |
if ((eh = e.hash) == MOVED) { |
1126 |
dl |
1.38 |
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 |
dl |
1.1 |
} |
1133 |
dl |
1.38 |
else if ((eh & HASH_BITS) == h && (ev = e.val) != null && |
1134 |
|
|
((ek = e.key) == k || k.equals(ek))) |
1135 |
dl |
1.24 |
return ev; |
1136 |
dl |
1.1 |
} |
1137 |
|
|
break; |
1138 |
|
|
} |
1139 |
|
|
return null; |
1140 |
|
|
} |
1141 |
|
|
|
1142 |
dl |
1.27 |
/** |
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 |
dl |
1.38 |
Node f; int i, fh; Object fk; |
1152 |
dl |
1.27 |
if (tab == null || |
1153 |
|
|
(f = tabAt(tab, i = (tab.length - 1) & h)) == null) |
1154 |
|
|
break; |
1155 |
dl |
1.38 |
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 |
dl |
1.27 |
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 |
jsr166 |
1.30 |
synchronized (f) { f.notifyAll(); }; |
1227 |
dl |
1.27 |
} |
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 |
dl |
1.38 |
* 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 |
dl |
1.27 |
* |
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 |
dl |
1.1 |
int h = spread(k.hashCode()); |
1268 |
dl |
1.38 |
int count = 0; |
1269 |
dl |
1.14 |
for (Node[] tab = table;;) { |
1270 |
dl |
1.38 |
int i; Node f; int fh; Object fk; |
1271 |
dl |
1.1 |
if (tab == null) |
1272 |
dl |
1.24 |
tab = initTable(); |
1273 |
|
|
else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) { |
1274 |
dl |
1.2 |
if (casTabAt(tab, i, null, new Node(h, k, v, null))) |
1275 |
dl |
1.14 |
break; // no lock when adding to empty bin |
1276 |
|
|
} |
1277 |
dl |
1.38 |
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 |
dl |
1.27 |
else if ((fh & LOCKED) != 0) { |
1304 |
|
|
checkForResize(); |
1305 |
|
|
f.tryAwaitLock(tab, i); |
1306 |
dl |
1.1 |
} |
1307 |
dl |
1.24 |
else if (f.casHash(fh, fh | LOCKED)) { |
1308 |
dl |
1.27 |
Object oldVal = null; |
1309 |
|
|
try { // needed in case equals() throws |
1310 |
dl |
1.24 |
if (tabAt(tab, i) == f) { |
1311 |
dl |
1.38 |
count = 1; |
1312 |
|
|
for (Node e = f;; ++count) { |
1313 |
dl |
1.24 |
Object ek, ev; |
1314 |
|
|
if ((e.hash & HASH_BITS) == h && |
1315 |
|
|
(ev = e.val) != null && |
1316 |
|
|
((ek = e.key) == k || k.equals(ek))) { |
1317 |
dl |
1.1 |
oldVal = ev; |
1318 |
dl |
1.27 |
e.val = v; |
1319 |
dl |
1.10 |
break; |
1320 |
dl |
1.1 |
} |
1321 |
dl |
1.10 |
Node last = e; |
1322 |
|
|
if ((e = e.next) == null) { |
1323 |
dl |
1.2 |
last.next = new Node(h, k, v, null); |
1324 |
dl |
1.38 |
if (count >= TREE_THRESHOLD) |
1325 |
|
|
replaceWithTreeBin(tab, i, k); |
1326 |
dl |
1.10 |
break; |
1327 |
dl |
1.1 |
} |
1328 |
|
|
} |
1329 |
|
|
} |
1330 |
dl |
1.24 |
} finally { // unlock and signal if needed |
1331 |
|
|
if (!f.casHash(fh | LOCKED, fh)) { |
1332 |
|
|
f.hash = fh; |
1333 |
jsr166 |
1.26 |
synchronized (f) { f.notifyAll(); }; |
1334 |
dl |
1.24 |
} |
1335 |
dl |
1.1 |
} |
1336 |
dl |
1.38 |
if (count != 0) { |
1337 |
dl |
1.27 |
if (oldVal != null) |
1338 |
|
|
return oldVal; |
1339 |
dl |
1.38 |
if (tab.length <= 64) |
1340 |
|
|
count = 2; |
1341 |
dl |
1.1 |
break; |
1342 |
|
|
} |
1343 |
|
|
} |
1344 |
|
|
} |
1345 |
dl |
1.27 |
counter.add(1L); |
1346 |
dl |
1.38 |
if (count > 1) |
1347 |
dl |
1.27 |
checkForResize(); |
1348 |
|
|
return null; |
1349 |
dl |
1.1 |
} |
1350 |
|
|
|
1351 |
dl |
1.27 |
/** Implementation for putIfAbsent */ |
1352 |
|
|
private final Object internalPutIfAbsent(Object k, Object v) { |
1353 |
dl |
1.1 |
int h = spread(k.hashCode()); |
1354 |
dl |
1.38 |
int count = 0; |
1355 |
dl |
1.14 |
for (Node[] tab = table;;) { |
1356 |
dl |
1.27 |
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 |
dl |
1.38 |
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 |
dl |
1.27 |
else if ((fh & HASH_BITS) == h && (fv = f.val) != null && |
1388 |
|
|
((fk = f.key) == k || k.equals(fk))) |
1389 |
|
|
return fv; |
1390 |
|
|
else { |
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 |
dl |
1.38 |
count = 1; |
1413 |
|
|
for (Node e = f;; ++count) { |
1414 |
dl |
1.27 |
Object ek, ev; |
1415 |
|
|
if ((e.hash & HASH_BITS) == h && |
1416 |
|
|
(ev = e.val) != null && |
1417 |
|
|
((ek = e.key) == k || k.equals(ek))) { |
1418 |
dl |
1.1 |
oldVal = ev; |
1419 |
dl |
1.27 |
break; |
1420 |
|
|
} |
1421 |
|
|
Node last = e; |
1422 |
|
|
if ((e = e.next) == null) { |
1423 |
|
|
last.next = new Node(h, k, v, null); |
1424 |
dl |
1.38 |
if (count >= TREE_THRESHOLD) |
1425 |
|
|
replaceWithTreeBin(tab, i, k); |
1426 |
dl |
1.27 |
break; |
1427 |
dl |
1.1 |
} |
1428 |
|
|
} |
1429 |
dl |
1.27 |
} |
1430 |
|
|
} finally { |
1431 |
|
|
if (!f.casHash(fh | LOCKED, fh)) { |
1432 |
|
|
f.hash = fh; |
1433 |
jsr166 |
1.30 |
synchronized (f) { f.notifyAll(); }; |
1434 |
dl |
1.24 |
} |
1435 |
|
|
} |
1436 |
dl |
1.38 |
if (count != 0) { |
1437 |
dl |
1.27 |
if (oldVal != null) |
1438 |
|
|
return oldVal; |
1439 |
dl |
1.38 |
if (tab.length <= 64) |
1440 |
|
|
count = 2; |
1441 |
dl |
1.27 |
break; |
1442 |
|
|
} |
1443 |
|
|
} |
1444 |
|
|
} |
1445 |
|
|
} |
1446 |
|
|
counter.add(1L); |
1447 |
dl |
1.38 |
if (count > 1) |
1448 |
|
|
checkForResize(); |
1449 |
dl |
1.27 |
return null; |
1450 |
|
|
} |
1451 |
|
|
|
1452 |
|
|
/** Implementation for computeIfAbsent */ |
1453 |
|
|
private final Object internalComputeIfAbsent(K k, |
1454 |
|
|
MappingFunction<? super K, ?> mf) { |
1455 |
|
|
int h = spread(k.hashCode()); |
1456 |
|
|
Object val = null; |
1457 |
dl |
1.38 |
int count = 0; |
1458 |
dl |
1.27 |
for (Node[] tab = table;;) { |
1459 |
|
|
Node f; int i, fh; Object fk, fv; |
1460 |
|
|
if (tab == null) |
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 |
dl |
1.38 |
count = 1; |
1466 |
dl |
1.27 |
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 |
jsr166 |
1.30 |
synchronized (node) { node.notifyAll(); }; |
1475 |
dl |
1.27 |
} |
1476 |
dl |
1.1 |
} |
1477 |
|
|
} |
1478 |
dl |
1.38 |
if (count != 0) |
1479 |
dl |
1.24 |
break; |
1480 |
dl |
1.27 |
} |
1481 |
dl |
1.38 |
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 |
|
|
} |
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 |
dl |
1.27 |
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 |
dl |
1.38 |
boolean added = false; |
1533 |
dl |
1.27 |
try { |
1534 |
|
|
if (tabAt(tab, i) == f) { |
1535 |
dl |
1.38 |
count = 1; |
1536 |
|
|
for (Node e = f;; ++count) { |
1537 |
dl |
1.27 |
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 |
dl |
1.38 |
if ((val = mf.map(k)) != null) { |
1547 |
|
|
added = true; |
1548 |
dl |
1.27 |
last.next = new Node(h, k, val, null); |
1549 |
dl |
1.38 |
if (count >= TREE_THRESHOLD) |
1550 |
|
|
replaceWithTreeBin(tab, i, k); |
1551 |
|
|
} |
1552 |
dl |
1.27 |
break; |
1553 |
|
|
} |
1554 |
|
|
} |
1555 |
|
|
} |
1556 |
|
|
} finally { |
1557 |
|
|
if (!f.casHash(fh | LOCKED, fh)) { |
1558 |
|
|
f.hash = fh; |
1559 |
jsr166 |
1.30 |
synchronized (f) { f.notifyAll(); }; |
1560 |
dl |
1.27 |
} |
1561 |
|
|
} |
1562 |
dl |
1.38 |
if (count != 0) { |
1563 |
|
|
if (!added) |
1564 |
|
|
return val; |
1565 |
|
|
if (tab.length <= 64) |
1566 |
|
|
count = 2; |
1567 |
dl |
1.27 |
break; |
1568 |
dl |
1.38 |
} |
1569 |
dl |
1.1 |
} |
1570 |
|
|
} |
1571 |
|
|
} |
1572 |
dl |
1.41 |
if (val != null) { |
1573 |
|
|
counter.add(1L); |
1574 |
|
|
if (count > 1) |
1575 |
|
|
checkForResize(); |
1576 |
|
|
} |
1577 |
dl |
1.27 |
return val; |
1578 |
dl |
1.1 |
} |
1579 |
|
|
|
1580 |
dl |
1.27 |
/** Implementation for compute */ |
1581 |
dl |
1.1 |
@SuppressWarnings("unchecked") |
1582 |
dl |
1.27 |
private final Object internalCompute(K k, |
1583 |
|
|
RemappingFunction<? super K, V> mf) { |
1584 |
dl |
1.1 |
int h = spread(k.hashCode()); |
1585 |
dl |
1.27 |
Object val = null; |
1586 |
dl |
1.41 |
int delta = 0; |
1587 |
dl |
1.38 |
int count = 0; |
1588 |
dl |
1.27 |
for (Node[] tab = table;;) { |
1589 |
dl |
1.38 |
Node f; int i, fh; Object fk; |
1590 |
dl |
1.1 |
if (tab == null) |
1591 |
dl |
1.24 |
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 |
dl |
1.38 |
count = 1; |
1597 |
dl |
1.27 |
if ((val = mf.remap(k, null)) != null) { |
1598 |
dl |
1.24 |
node.val = val; |
1599 |
dl |
1.41 |
delta = 1; |
1600 |
dl |
1.24 |
} |
1601 |
|
|
} finally { |
1602 |
dl |
1.41 |
if (delta == 0) |
1603 |
dl |
1.24 |
setTabAt(tab, i, null); |
1604 |
|
|
if (!node.casHash(fh, h)) { |
1605 |
dl |
1.25 |
node.hash = h; |
1606 |
jsr166 |
1.26 |
synchronized (node) { node.notifyAll(); }; |
1607 |
dl |
1.1 |
} |
1608 |
|
|
} |
1609 |
|
|
} |
1610 |
dl |
1.38 |
if (count != 0) |
1611 |
dl |
1.10 |
break; |
1612 |
dl |
1.1 |
} |
1613 |
dl |
1.38 |
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 |
jsr166 |
1.39 |
Object pv = (p == null) ? null : p.val; |
1622 |
dl |
1.38 |
if ((val = mf.remap(k, (V)pv)) != null) { |
1623 |
|
|
if (p != null) |
1624 |
|
|
p.val = val; |
1625 |
|
|
else { |
1626 |
|
|
count = 2; |
1627 |
dl |
1.41 |
delta = 1; |
1628 |
dl |
1.38 |
t.putTreeNode(h, k, val); |
1629 |
|
|
} |
1630 |
|
|
} |
1631 |
dl |
1.41 |
else if (p != null) { |
1632 |
|
|
delta = -1; |
1633 |
|
|
t.deleteTreeNode(p); |
1634 |
|
|
} |
1635 |
dl |
1.38 |
} |
1636 |
|
|
} finally { |
1637 |
|
|
t.release(0); |
1638 |
|
|
} |
1639 |
|
|
if (count != 0) |
1640 |
|
|
break; |
1641 |
|
|
} |
1642 |
|
|
else |
1643 |
|
|
tab = (Node[])fk; |
1644 |
|
|
} |
1645 |
dl |
1.27 |
else if ((fh & LOCKED) != 0) { |
1646 |
|
|
checkForResize(); |
1647 |
|
|
f.tryAwaitLock(tab, i); |
1648 |
dl |
1.14 |
} |
1649 |
dl |
1.24 |
else if (f.casHash(fh, fh | LOCKED)) { |
1650 |
|
|
try { |
1651 |
|
|
if (tabAt(tab, i) == f) { |
1652 |
dl |
1.38 |
count = 1; |
1653 |
dl |
1.41 |
for (Node e = f, pred = null;; ++count) { |
1654 |
dl |
1.27 |
Object ek, ev; |
1655 |
dl |
1.24 |
if ((e.hash & HASH_BITS) == h && |
1656 |
|
|
(ev = e.val) != null && |
1657 |
|
|
((ek = e.key) == k || k.equals(ek))) { |
1658 |
dl |
1.27 |
val = mf.remap(k, (V)ev); |
1659 |
|
|
if (val != null) |
1660 |
|
|
e.val = val; |
1661 |
dl |
1.41 |
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 |
dl |
1.10 |
break; |
1670 |
dl |
1.1 |
} |
1671 |
dl |
1.41 |
pred = e; |
1672 |
dl |
1.10 |
if ((e = e.next) == null) { |
1673 |
dl |
1.27 |
if ((val = mf.remap(k, null)) != null) { |
1674 |
dl |
1.41 |
pred.next = new Node(h, k, val, null); |
1675 |
|
|
delta = 1; |
1676 |
dl |
1.38 |
if (count >= TREE_THRESHOLD) |
1677 |
|
|
replaceWithTreeBin(tab, i, k); |
1678 |
dl |
1.1 |
} |
1679 |
dl |
1.10 |
break; |
1680 |
dl |
1.1 |
} |
1681 |
|
|
} |
1682 |
|
|
} |
1683 |
dl |
1.24 |
} finally { |
1684 |
|
|
if (!f.casHash(fh | LOCKED, fh)) { |
1685 |
|
|
f.hash = fh; |
1686 |
jsr166 |
1.26 |
synchronized (f) { f.notifyAll(); }; |
1687 |
dl |
1.24 |
} |
1688 |
dl |
1.1 |
} |
1689 |
dl |
1.38 |
if (count != 0) { |
1690 |
|
|
if (tab.length <= 64) |
1691 |
|
|
count = 2; |
1692 |
dl |
1.10 |
break; |
1693 |
dl |
1.38 |
} |
1694 |
dl |
1.1 |
} |
1695 |
dl |
1.10 |
} |
1696 |
dl |
1.41 |
if (delta != 0) { |
1697 |
|
|
counter.add((long)delta); |
1698 |
dl |
1.38 |
if (count > 1) |
1699 |
dl |
1.27 |
checkForResize(); |
1700 |
|
|
} |
1701 |
dl |
1.1 |
return val; |
1702 |
|
|
} |
1703 |
|
|
|
1704 |
dl |
1.27 |
/** 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 |
dl |
1.38 |
int i; Node f; int fh; Object fk; |
1720 |
dl |
1.27 |
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 |
dl |
1.38 |
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 |
dl |
1.27 |
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 |
dl |
1.38 |
int count = 0; |
1761 |
dl |
1.27 |
try { |
1762 |
|
|
if (tabAt(tab, i) == f) { |
1763 |
dl |
1.38 |
count = 1; |
1764 |
|
|
for (Node e = f;; ++count) { |
1765 |
dl |
1.27 |
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 |
dl |
1.38 |
if (count >= TREE_THRESHOLD) |
1777 |
|
|
replaceWithTreeBin(tab, i, k); |
1778 |
dl |
1.27 |
break; |
1779 |
|
|
} |
1780 |
|
|
} |
1781 |
|
|
} |
1782 |
|
|
} finally { |
1783 |
|
|
if (!f.casHash(fh | LOCKED, fh)) { |
1784 |
|
|
f.hash = fh; |
1785 |
jsr166 |
1.30 |
synchronized (f) { f.notifyAll(); }; |
1786 |
dl |
1.27 |
} |
1787 |
|
|
} |
1788 |
dl |
1.38 |
if (count != 0) { |
1789 |
|
|
if (count > 1) { |
1790 |
dl |
1.27 |
counter.add(delta); |
1791 |
|
|
delta = 0L; |
1792 |
|
|
checkForResize(); |
1793 |
dl |
1.1 |
} |
1794 |
dl |
1.27 |
break; |
1795 |
dl |
1.24 |
} |
1796 |
|
|
} |
1797 |
dl |
1.1 |
} |
1798 |
|
|
} |
1799 |
dl |
1.27 |
} finally { |
1800 |
|
|
if (delta != 0) |
1801 |
|
|
counter.add(delta); |
1802 |
dl |
1.1 |
} |
1803 |
dl |
1.27 |
if (npe) |
1804 |
|
|
throw new NullPointerException(); |
1805 |
dl |
1.1 |
} |
1806 |
|
|
|
1807 |
dl |
1.27 |
/* ---------------- Table Initialization and Resizing -------------- */ |
1808 |
dl |
1.24 |
|
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 |
dl |
1.27 |
sc = n - (n >>> 2); |
1837 |
dl |
1.24 |
} |
1838 |
|
|
} finally { |
1839 |
|
|
sizeCtl = sc; |
1840 |
|
|
} |
1841 |
|
|
break; |
1842 |
|
|
} |
1843 |
|
|
} |
1844 |
|
|
return tab; |
1845 |
|
|
} |
1846 |
|
|
|
1847 |
|
|
/** |
1848 |
dl |
1.27 |
* 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 |
dl |
1.24 |
try { |
1860 |
dl |
1.27 |
if (tab == table) { |
1861 |
dl |
1.24 |
table = rebuild(tab); |
1862 |
dl |
1.27 |
sc = (n << 1) - (n >>> 1); |
1863 |
dl |
1.24 |
} |
1864 |
|
|
} finally { |
1865 |
|
|
sizeCtl = sc; |
1866 |
|
|
} |
1867 |
|
|
} |
1868 |
|
|
} |
1869 |
|
|
|
1870 |
dl |
1.27 |
/** |
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 |
jsr166 |
1.30 |
n = (sc > c) ? sc : c; |
1883 |
dl |
1.27 |
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 |
dl |
1.24 |
/* |
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 |
jsr166 |
1.33 |
Node g = new Node(MOVED|LOCKED, nextTab, null, null); |
1934 |
dl |
1.24 |
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 |
jsr166 |
1.26 |
synchronized (g) { g.notifyAll(); } |
1942 |
dl |
1.24 |
} |
1943 |
|
|
} |
1944 |
|
|
} |
1945 |
dl |
1.38 |
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 |
dl |
1.24 |
boolean validated = false; |
1966 |
|
|
try { // split to lo and hi lists; copying as needed |
1967 |
|
|
if (tabAt(tab, i) == f) { |
1968 |
|
|
validated = true; |
1969 |
dl |
1.38 |
splitBin(nextTab, i, f); |
1970 |
dl |
1.24 |
setTabAt(tab, i, fwd); |
1971 |
|
|
} |
1972 |
|
|
} finally { |
1973 |
|
|
if (!f.casHash(fh | LOCKED, fh)) { |
1974 |
|
|
f.hash = fh; |
1975 |
jsr166 |
1.26 |
synchronized (f) { f.notifyAll(); }; |
1976 |
dl |
1.24 |
} |
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 |
dl |
1.27 |
/** |
2015 |
dl |
1.38 |
* 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 |
dl |
1.27 |
* 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 |
dl |
1.38 |
int fh; Object fk; |
2094 |
dl |
1.27 |
Node f = tabAt(tab, i); |
2095 |
|
|
if (f == null) |
2096 |
|
|
++i; |
2097 |
dl |
1.38 |
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 |
|
|
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 |
dl |
1.27 |
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 |
dl |
1.38 |
e.val = null; |
2128 |
|
|
--delta; |
2129 |
dl |
1.27 |
} |
2130 |
|
|
setTabAt(tab, i, null); |
2131 |
dl |
1.38 |
++i; |
2132 |
dl |
1.27 |
} |
2133 |
|
|
} finally { |
2134 |
|
|
if (!f.casHash(fh | LOCKED, fh)) { |
2135 |
|
|
f.hash = fh; |
2136 |
jsr166 |
1.30 |
synchronized (f) { f.notifyAll(); }; |
2137 |
dl |
1.27 |
} |
2138 |
|
|
} |
2139 |
|
|
} |
2140 |
|
|
} |
2141 |
|
|
if (delta != 0) |
2142 |
|
|
counter.add(delta); |
2143 |
|
|
} |
2144 |
|
|
|
2145 |
dl |
1.14 |
/* ----------------Table Traversal -------------- */ |
2146 |
|
|
|
2147 |
dl |
1.1 |
/** |
2148 |
dl |
1.14 |
* Encapsulates traversal for methods such as containsValue; also |
2149 |
|
|
* serves as a base class for other iterators. |
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 |
jsr166 |
1.36 |
* snapshot, has a non-null user value). Because val fields can |
2154 |
dl |
1.14 |
* 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 |
dl |
1.41 |
* {@code while (it.advance() != null) { process(it.nextKey); }} |
2161 |
dl |
1.14 |
* |
2162 |
dl |
1.41 |
* 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 |
dl |
1.14 |
* |
2167 |
dl |
1.27 |
* 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 |
dl |
1.14 |
* |
2176 |
|
|
* Normally, iteration proceeds bin-by-bin traversing lists. |
2177 |
|
|
* However, if the table has been resized, then all future steps |
2178 |
|
|
* must traverse both the bin at the current index as well as at |
2179 |
|
|
* (index + baseSize); and so on for further resizings. To |
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. |
2183 |
|
|
*/ |
2184 |
dl |
1.41 |
static class InternalIterator<K,V> { |
2185 |
|
|
final ConcurrentHashMapV8<K, V> map; |
2186 |
dl |
1.14 |
Node next; // the next entry to use |
2187 |
|
|
Node last; // the last entry used |
2188 |
|
|
Object nextKey; // cached key field of next |
2189 |
|
|
Object nextVal; // cached val 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 |
dl |
1.41 |
int baseLimit; // index bound for initial table |
2194 |
dl |
1.14 |
final int baseSize; // initial table size |
2195 |
|
|
|
2196 |
|
|
/** Creates iterator for all entries in the table. */ |
2197 |
dl |
1.41 |
InternalIterator(ConcurrentHashMapV8<K, V> map) { |
2198 |
|
|
this.tab = (this.map = map).table; |
2199 |
dl |
1.14 |
baseLimit = baseSize = (tab == null) ? 0 : tab.length; |
2200 |
|
|
} |
2201 |
|
|
|
2202 |
dl |
1.41 |
/** 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 |
dl |
1.14 |
Node e = last = next; |
2219 |
dl |
1.41 |
Object ev = null; |
2220 |
dl |
1.14 |
outer: do { |
2221 |
dl |
1.24 |
if (e != null) // advance past used/skipped node |
2222 |
dl |
1.1 |
e = e.next; |
2223 |
dl |
1.24 |
while (e == null) { // get to next non-null bin |
2224 |
dl |
1.38 |
Node[] t; int b, i, n; Object ek; // checks must use locals |
2225 |
dl |
1.14 |
if ((b = baseIndex) >= baseLimit || (i = index) < 0 || |
2226 |
|
|
(t = tab) == null || i >= (n = t.length)) |
2227 |
|
|
break outer; |
2228 |
dl |
1.38 |
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 |
dl |
1.1 |
} |
2238 |
dl |
1.14 |
nextKey = e.key; |
2239 |
dl |
1.41 |
} while ((ev = e.val) == null); // skip deleted or special nodes |
2240 |
dl |
1.14 |
next = e; |
2241 |
dl |
1.41 |
return nextVal = ev; |
2242 |
dl |
1.1 |
} |
2243 |
dl |
1.41 |
|
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 |
dl |
1.1 |
} |
2260 |
|
|
|
2261 |
|
|
/* ---------------- Public operations -------------- */ |
2262 |
|
|
|
2263 |
|
|
/** |
2264 |
dl |
1.16 |
* Creates a new, empty map with the default initial table size (16), |
2265 |
dl |
1.1 |
*/ |
2266 |
dl |
1.16 |
public ConcurrentHashMapV8() { |
2267 |
dl |
1.14 |
this.counter = new LongAdder(); |
2268 |
dl |
1.1 |
} |
2269 |
|
|
|
2270 |
|
|
/** |
2271 |
dl |
1.16 |
* 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 |
dl |
1.1 |
* |
2275 |
|
|
* @param initialCapacity The implementation performs internal |
2276 |
|
|
* sizing to accommodate this many elements. |
2277 |
|
|
* @throws IllegalArgumentException if the initial capacity of |
2278 |
jsr166 |
1.18 |
* elements is negative |
2279 |
dl |
1.1 |
*/ |
2280 |
dl |
1.16 |
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 |
dl |
1.24 |
this.sizeCtl = cap; |
2288 |
dl |
1.1 |
} |
2289 |
|
|
|
2290 |
|
|
/** |
2291 |
dl |
1.16 |
* Creates a new map with the same mappings as the given map. |
2292 |
dl |
1.1 |
* |
2293 |
dl |
1.16 |
* @param m the map |
2294 |
dl |
1.1 |
*/ |
2295 |
dl |
1.16 |
public ConcurrentHashMapV8(Map<? extends K, ? extends V> m) { |
2296 |
|
|
this.counter = new LongAdder(); |
2297 |
dl |
1.24 |
this.sizeCtl = DEFAULT_CAPACITY; |
2298 |
dl |
1.27 |
internalPutAll(m); |
2299 |
dl |
1.1 |
} |
2300 |
|
|
|
2301 |
|
|
/** |
2302 |
dl |
1.16 |
* 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 |
jsr166 |
1.18 |
* establishing the initial table size |
2311 |
dl |
1.16 |
* @throws IllegalArgumentException if the initial capacity of |
2312 |
|
|
* elements is negative or the load factor is nonpositive |
2313 |
jsr166 |
1.22 |
* |
2314 |
|
|
* @since 1.6 |
2315 |
dl |
1.1 |
*/ |
2316 |
dl |
1.16 |
public ConcurrentHashMapV8(int initialCapacity, float loadFactor) { |
2317 |
|
|
this(initialCapacity, loadFactor, 1); |
2318 |
dl |
1.1 |
} |
2319 |
|
|
|
2320 |
|
|
/** |
2321 |
dl |
1.16 |
* 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 |
dl |
1.1 |
* |
2326 |
dl |
1.16 |
* @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 |
jsr166 |
1.18 |
* establishing the initial table size |
2331 |
dl |
1.16 |
* @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 |
jsr166 |
1.18 |
* nonpositive |
2337 |
dl |
1.1 |
*/ |
2338 |
dl |
1.16 |
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 |
jsr166 |
1.33 |
int cap = ((size >= (long)MAXIMUM_CAPACITY) ? |
2346 |
|
|
MAXIMUM_CAPACITY: tableSizeFor((int)size)); |
2347 |
dl |
1.16 |
this.counter = new LongAdder(); |
2348 |
dl |
1.24 |
this.sizeCtl = cap; |
2349 |
dl |
1.1 |
} |
2350 |
|
|
|
2351 |
|
|
/** |
2352 |
dl |
1.14 |
* {@inheritDoc} |
2353 |
dl |
1.1 |
*/ |
2354 |
|
|
public boolean isEmpty() { |
2355 |
dl |
1.2 |
return counter.sum() <= 0L; // ignore transient negative values |
2356 |
dl |
1.1 |
} |
2357 |
|
|
|
2358 |
|
|
/** |
2359 |
dl |
1.14 |
* {@inheritDoc} |
2360 |
dl |
1.1 |
*/ |
2361 |
|
|
public int size() { |
2362 |
|
|
long n = counter.sum(); |
2363 |
jsr166 |
1.15 |
return ((n < 0L) ? 0 : |
2364 |
|
|
(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE : |
2365 |
dl |
1.14 |
(int)n); |
2366 |
dl |
1.1 |
} |
2367 |
|
|
|
2368 |
dl |
1.24 |
final long longSize() { // accurate version of size needed for views |
2369 |
|
|
long n = counter.sum(); |
2370 |
|
|
return (n < 0L) ? 0L : n; |
2371 |
|
|
} |
2372 |
|
|
|
2373 |
dl |
1.1 |
/** |
2374 |
|
|
* Returns the value to which the specified key is mapped, |
2375 |
|
|
* or {@code null} if this map contains no mapping for the key. |
2376 |
|
|
* |
2377 |
|
|
* <p>More formally, if this map contains a mapping from a key |
2378 |
|
|
* {@code k} to a value {@code v} such that {@code key.equals(k)}, |
2379 |
|
|
* then this method returns {@code v}; otherwise it returns |
2380 |
|
|
* {@code null}. (There can be at most one such mapping.) |
2381 |
|
|
* |
2382 |
|
|
* @throws NullPointerException if the specified key is null |
2383 |
|
|
*/ |
2384 |
|
|
@SuppressWarnings("unchecked") |
2385 |
|
|
public V get(Object key) { |
2386 |
|
|
if (key == null) |
2387 |
|
|
throw new NullPointerException(); |
2388 |
|
|
return (V)internalGet(key); |
2389 |
|
|
} |
2390 |
|
|
|
2391 |
|
|
/** |
2392 |
|
|
* Tests if the specified object is a key in this table. |
2393 |
|
|
* |
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 |
jsr166 |
1.18 |
* {@code equals} method; {@code false} otherwise |
2398 |
dl |
1.1 |
* @throws NullPointerException if the specified key is null |
2399 |
|
|
*/ |
2400 |
|
|
public boolean containsKey(Object key) { |
2401 |
|
|
if (key == null) |
2402 |
|
|
throw new NullPointerException(); |
2403 |
|
|
return internalGet(key) != null; |
2404 |
|
|
} |
2405 |
|
|
|
2406 |
|
|
/** |
2407 |
|
|
* Returns {@code true} if this map maps one or more keys to the |
2408 |
dl |
1.14 |
* specified value. Note: This method may require a full traversal |
2409 |
|
|
* of the map, and is much slower than method {@code containsKey}. |
2410 |
dl |
1.1 |
* |
2411 |
|
|
* @param value value whose presence in this map is to be tested |
2412 |
|
|
* @return {@code true} if this map maps one or more keys to the |
2413 |
|
|
* specified value |
2414 |
|
|
* @throws NullPointerException if the specified value is null |
2415 |
|
|
*/ |
2416 |
|
|
public boolean containsValue(Object value) { |
2417 |
|
|
if (value == null) |
2418 |
|
|
throw new NullPointerException(); |
2419 |
dl |
1.14 |
Object v; |
2420 |
dl |
1.41 |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
2421 |
|
|
while ((v = it.advance()) != null) { |
2422 |
|
|
if (v == value || value.equals(v)) |
2423 |
dl |
1.14 |
return true; |
2424 |
|
|
} |
2425 |
|
|
return false; |
2426 |
dl |
1.1 |
} |
2427 |
|
|
|
2428 |
|
|
/** |
2429 |
|
|
* Legacy method testing if some key maps into the specified value |
2430 |
|
|
* in this table. This method is identical in functionality to |
2431 |
|
|
* {@link #containsValue}, and exists solely to ensure |
2432 |
|
|
* full compatibility with class {@link java.util.Hashtable}, |
2433 |
|
|
* which supported this method prior to introduction of the |
2434 |
|
|
* Java Collections framework. |
2435 |
|
|
* |
2436 |
|
|
* @param value a value to search for |
2437 |
|
|
* @return {@code true} if and only if some key maps to the |
2438 |
|
|
* {@code value} argument in this table as |
2439 |
|
|
* determined by the {@code equals} method; |
2440 |
|
|
* {@code false} otherwise |
2441 |
|
|
* @throws NullPointerException if the specified value is null |
2442 |
|
|
*/ |
2443 |
|
|
public boolean contains(Object value) { |
2444 |
|
|
return containsValue(value); |
2445 |
|
|
} |
2446 |
|
|
|
2447 |
|
|
/** |
2448 |
|
|
* Maps the specified key to the specified value in this table. |
2449 |
|
|
* Neither the key nor the value can be null. |
2450 |
|
|
* |
2451 |
|
|
* <p> The value can be retrieved by calling the {@code get} method |
2452 |
|
|
* with a key that is equal to the original key. |
2453 |
|
|
* |
2454 |
|
|
* @param key key with which the specified value is to be associated |
2455 |
|
|
* @param value value to be associated with the specified key |
2456 |
|
|
* @return the previous value associated with {@code key}, or |
2457 |
|
|
* {@code null} if there was no mapping for {@code key} |
2458 |
|
|
* @throws NullPointerException if the specified key or value is null |
2459 |
|
|
*/ |
2460 |
|
|
@SuppressWarnings("unchecked") |
2461 |
|
|
public V put(K key, V value) { |
2462 |
|
|
if (key == null || value == null) |
2463 |
|
|
throw new NullPointerException(); |
2464 |
dl |
1.27 |
return (V)internalPut(key, value); |
2465 |
dl |
1.1 |
} |
2466 |
|
|
|
2467 |
|
|
/** |
2468 |
|
|
* {@inheritDoc} |
2469 |
|
|
* |
2470 |
|
|
* @return the previous value associated with the specified key, |
2471 |
|
|
* or {@code null} if there was no mapping for the key |
2472 |
|
|
* @throws NullPointerException if the specified key or value is null |
2473 |
|
|
*/ |
2474 |
|
|
@SuppressWarnings("unchecked") |
2475 |
|
|
public V putIfAbsent(K key, V value) { |
2476 |
|
|
if (key == null || value == null) |
2477 |
|
|
throw new NullPointerException(); |
2478 |
dl |
1.27 |
return (V)internalPutIfAbsent(key, value); |
2479 |
dl |
1.1 |
} |
2480 |
|
|
|
2481 |
|
|
/** |
2482 |
|
|
* Copies all of the mappings from the specified map to this one. |
2483 |
|
|
* These mappings replace any mappings that this map had for any of the |
2484 |
|
|
* keys currently in the specified map. |
2485 |
|
|
* |
2486 |
|
|
* @param m mappings to be stored in this map |
2487 |
|
|
*/ |
2488 |
|
|
public void putAll(Map<? extends K, ? extends V> m) { |
2489 |
dl |
1.27 |
internalPutAll(m); |
2490 |
dl |
1.1 |
} |
2491 |
|
|
|
2492 |
|
|
/** |
2493 |
|
|
* If the specified key is not already associated with a value, |
2494 |
dl |
1.41 |
* computes its value using the given mappingFunction and enters |
2495 |
|
|
* it into the map unless null. This is equivalent to |
2496 |
dl |
1.27 |
* <pre> {@code |
2497 |
jsr166 |
1.13 |
* if (map.containsKey(key)) |
2498 |
|
|
* return map.get(key); |
2499 |
|
|
* value = mappingFunction.map(key); |
2500 |
dl |
1.41 |
* if (value != null) |
2501 |
|
|
* map.put(key, value); |
2502 |
jsr166 |
1.13 |
* return value;}</pre> |
2503 |
dl |
1.1 |
* |
2504 |
dl |
1.27 |
* except that the action is performed atomically. If the |
2505 |
dl |
1.41 |
* 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 |
dl |
1.27 |
* |
2515 |
jsr166 |
1.13 |
* <pre> {@code |
2516 |
dl |
1.5 |
* map.computeIfAbsent(key, new MappingFunction<K, V>() { |
2517 |
jsr166 |
1.13 |
* public V map(K k) { return new Value(f(k)); }});}</pre> |
2518 |
dl |
1.1 |
* |
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 |
dl |
1.41 |
* the specified key, or null if the computed value is null. |
2523 |
|
|
* @throws NullPointerException if the specified key or mappingFunction |
2524 |
|
|
* is null |
2525 |
dl |
1.5 |
* @throws IllegalStateException if the computation detectably |
2526 |
|
|
* attempts a recursive update to this map that would |
2527 |
jsr166 |
1.18 |
* otherwise never complete |
2528 |
dl |
1.1 |
* @throws RuntimeException or Error if the mappingFunction does so, |
2529 |
jsr166 |
1.18 |
* in which case the mapping is left unestablished |
2530 |
dl |
1.1 |
*/ |
2531 |
dl |
1.27 |
@SuppressWarnings("unchecked") |
2532 |
dl |
1.1 |
public V computeIfAbsent(K key, MappingFunction<? super K, ? extends V> mappingFunction) { |
2533 |
|
|
if (key == null || mappingFunction == null) |
2534 |
|
|
throw new NullPointerException(); |
2535 |
dl |
1.27 |
return (V)internalComputeIfAbsent(key, mappingFunction); |
2536 |
dl |
1.2 |
} |
2537 |
|
|
|
2538 |
|
|
/** |
2539 |
dl |
1.41 |
* Computes a new mapping value given a key and |
2540 |
dl |
1.27 |
* its current mapped value (or {@code null} if there is no current |
2541 |
|
|
* mapping). This is equivalent to |
2542 |
jsr166 |
1.13 |
* <pre> {@code |
2543 |
dl |
1.41 |
* value = remappingFunction.remap(key, map.get(key)); |
2544 |
|
|
* if (value != null) |
2545 |
|
|
* map.put(key, value); |
2546 |
|
|
* else |
2547 |
|
|
* map.remove(key); |
2548 |
dl |
1.27 |
* }</pre> |
2549 |
dl |
1.2 |
* |
2550 |
dl |
1.27 |
* except that the action is performed atomically. If the |
2551 |
dl |
1.41 |
* 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 |
dl |
1.27 |
* |
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 |
dl |
1.28 |
* return (v == null) ? msg : v + msg;});}}</pre> |
2566 |
dl |
1.2 |
* |
2567 |
|
|
* @param key key with which the specified value is to be associated |
2568 |
dl |
1.27 |
* @param remappingFunction the function to compute a value |
2569 |
|
|
* @return the new value associated with |
2570 |
dl |
1.41 |
* the specified key, or null if none. |
2571 |
dl |
1.27 |
* @throws NullPointerException if the specified key or remappingFunction |
2572 |
dl |
1.41 |
* is null |
2573 |
dl |
1.5 |
* @throws IllegalStateException if the computation detectably |
2574 |
|
|
* attempts a recursive update to this map that would |
2575 |
jsr166 |
1.18 |
* otherwise never complete |
2576 |
dl |
1.29 |
* @throws RuntimeException or Error if the remappingFunction does so, |
2577 |
jsr166 |
1.18 |
* in which case the mapping is unchanged |
2578 |
dl |
1.2 |
*/ |
2579 |
dl |
1.27 |
@SuppressWarnings("unchecked") |
2580 |
|
|
public V compute(K key, RemappingFunction<? super K, V> remappingFunction) { |
2581 |
|
|
if (key == null || remappingFunction == null) |
2582 |
dl |
1.2 |
throw new NullPointerException(); |
2583 |
dl |
1.27 |
return (V)internalCompute(key, remappingFunction); |
2584 |
dl |
1.1 |
} |
2585 |
|
|
|
2586 |
|
|
/** |
2587 |
|
|
* Removes the key (and its corresponding value) from this map. |
2588 |
|
|
* This method does nothing if the key is not in the map. |
2589 |
|
|
* |
2590 |
|
|
* @param key the key that needs to be removed |
2591 |
|
|
* @return the previous value associated with {@code key}, or |
2592 |
|
|
* {@code null} if there was no mapping for {@code key} |
2593 |
|
|
* @throws NullPointerException if the specified key is null |
2594 |
|
|
*/ |
2595 |
|
|
@SuppressWarnings("unchecked") |
2596 |
|
|
public V remove(Object key) { |
2597 |
|
|
if (key == null) |
2598 |
|
|
throw new NullPointerException(); |
2599 |
jsr166 |
1.3 |
return (V)internalReplace(key, null, null); |
2600 |
dl |
1.1 |
} |
2601 |
|
|
|
2602 |
|
|
/** |
2603 |
|
|
* {@inheritDoc} |
2604 |
|
|
* |
2605 |
|
|
* @throws NullPointerException if the specified key is null |
2606 |
|
|
*/ |
2607 |
|
|
public boolean remove(Object key, Object value) { |
2608 |
|
|
if (key == null) |
2609 |
|
|
throw new NullPointerException(); |
2610 |
|
|
if (value == null) |
2611 |
|
|
return false; |
2612 |
|
|
return internalReplace(key, null, value) != null; |
2613 |
|
|
} |
2614 |
|
|
|
2615 |
|
|
/** |
2616 |
|
|
* {@inheritDoc} |
2617 |
|
|
* |
2618 |
|
|
* @throws NullPointerException if any of the arguments are null |
2619 |
|
|
*/ |
2620 |
|
|
public boolean replace(K key, V oldValue, V newValue) { |
2621 |
|
|
if (key == null || oldValue == null || newValue == null) |
2622 |
|
|
throw new NullPointerException(); |
2623 |
jsr166 |
1.3 |
return internalReplace(key, newValue, oldValue) != null; |
2624 |
dl |
1.1 |
} |
2625 |
|
|
|
2626 |
|
|
/** |
2627 |
|
|
* {@inheritDoc} |
2628 |
|
|
* |
2629 |
|
|
* @return the previous value associated with the specified key, |
2630 |
|
|
* or {@code null} if there was no mapping for the key |
2631 |
|
|
* @throws NullPointerException if the specified key or value is null |
2632 |
|
|
*/ |
2633 |
|
|
@SuppressWarnings("unchecked") |
2634 |
|
|
public V replace(K key, V value) { |
2635 |
|
|
if (key == null || value == null) |
2636 |
|
|
throw new NullPointerException(); |
2637 |
jsr166 |
1.3 |
return (V)internalReplace(key, value, null); |
2638 |
dl |
1.1 |
} |
2639 |
|
|
|
2640 |
|
|
/** |
2641 |
|
|
* Removes all of the mappings from this map. |
2642 |
|
|
*/ |
2643 |
|
|
public void clear() { |
2644 |
|
|
internalClear(); |
2645 |
|
|
} |
2646 |
|
|
|
2647 |
|
|
/** |
2648 |
|
|
* Returns a {@link Set} view of the keys contained in this map. |
2649 |
|
|
* The set is backed by the map, so changes to the map are |
2650 |
|
|
* reflected in the set, and vice-versa. The set supports element |
2651 |
|
|
* removal, which removes the corresponding mapping from this map, |
2652 |
|
|
* via the {@code Iterator.remove}, {@code Set.remove}, |
2653 |
|
|
* {@code removeAll}, {@code retainAll}, and {@code clear} |
2654 |
|
|
* operations. It does not support the {@code add} or |
2655 |
|
|
* {@code addAll} operations. |
2656 |
|
|
* |
2657 |
|
|
* <p>The view's {@code iterator} is a "weakly consistent" iterator |
2658 |
|
|
* that will never throw {@link ConcurrentModificationException}, |
2659 |
|
|
* and guarantees to traverse elements as they existed upon |
2660 |
|
|
* construction of the iterator, and may (but is not guaranteed to) |
2661 |
|
|
* reflect any modifications subsequent to construction. |
2662 |
|
|
*/ |
2663 |
|
|
public Set<K> keySet() { |
2664 |
dl |
1.14 |
KeySet<K,V> ks = keySet; |
2665 |
|
|
return (ks != null) ? ks : (keySet = new KeySet<K,V>(this)); |
2666 |
dl |
1.1 |
} |
2667 |
|
|
|
2668 |
|
|
/** |
2669 |
|
|
* Returns a {@link Collection} view of the values contained in this map. |
2670 |
|
|
* The collection is backed by the map, so changes to the map are |
2671 |
|
|
* reflected in the collection, and vice-versa. The collection |
2672 |
|
|
* supports element removal, which removes the corresponding |
2673 |
|
|
* mapping from this map, via the {@code Iterator.remove}, |
2674 |
|
|
* {@code Collection.remove}, {@code removeAll}, |
2675 |
|
|
* {@code retainAll}, and {@code clear} operations. It does not |
2676 |
|
|
* support the {@code add} or {@code addAll} operations. |
2677 |
|
|
* |
2678 |
|
|
* <p>The view's {@code iterator} is a "weakly consistent" iterator |
2679 |
|
|
* that will never throw {@link ConcurrentModificationException}, |
2680 |
|
|
* and guarantees to traverse elements as they existed upon |
2681 |
|
|
* construction of the iterator, and may (but is not guaranteed to) |
2682 |
|
|
* reflect any modifications subsequent to construction. |
2683 |
|
|
*/ |
2684 |
|
|
public Collection<V> values() { |
2685 |
dl |
1.14 |
Values<K,V> vs = values; |
2686 |
|
|
return (vs != null) ? vs : (values = new Values<K,V>(this)); |
2687 |
dl |
1.1 |
} |
2688 |
|
|
|
2689 |
|
|
/** |
2690 |
|
|
* Returns a {@link Set} view of the mappings contained in this map. |
2691 |
|
|
* The set is backed by the map, so changes to the map are |
2692 |
|
|
* reflected in the set, and vice-versa. The set supports element |
2693 |
|
|
* removal, which removes the corresponding mapping from the map, |
2694 |
|
|
* via the {@code Iterator.remove}, {@code Set.remove}, |
2695 |
|
|
* {@code removeAll}, {@code retainAll}, and {@code clear} |
2696 |
|
|
* operations. It does not support the {@code add} or |
2697 |
|
|
* {@code addAll} operations. |
2698 |
|
|
* |
2699 |
|
|
* <p>The view's {@code iterator} is a "weakly consistent" iterator |
2700 |
|
|
* that will never throw {@link ConcurrentModificationException}, |
2701 |
|
|
* and guarantees to traverse elements as they existed upon |
2702 |
|
|
* construction of the iterator, and may (but is not guaranteed to) |
2703 |
|
|
* reflect any modifications subsequent to construction. |
2704 |
|
|
*/ |
2705 |
|
|
public Set<Map.Entry<K,V>> entrySet() { |
2706 |
dl |
1.14 |
EntrySet<K,V> es = entrySet; |
2707 |
|
|
return (es != null) ? es : (entrySet = new EntrySet<K,V>(this)); |
2708 |
dl |
1.1 |
} |
2709 |
|
|
|
2710 |
|
|
/** |
2711 |
|
|
* Returns an enumeration of the keys in this table. |
2712 |
|
|
* |
2713 |
|
|
* @return an enumeration of the keys in this table |
2714 |
|
|
* @see #keySet() |
2715 |
|
|
*/ |
2716 |
|
|
public Enumeration<K> keys() { |
2717 |
dl |
1.14 |
return new KeyIterator<K,V>(this); |
2718 |
dl |
1.1 |
} |
2719 |
|
|
|
2720 |
|
|
/** |
2721 |
|
|
* Returns an enumeration of the values in this table. |
2722 |
|
|
* |
2723 |
|
|
* @return an enumeration of the values in this table |
2724 |
|
|
* @see #values() |
2725 |
|
|
*/ |
2726 |
|
|
public Enumeration<V> elements() { |
2727 |
dl |
1.14 |
return new ValueIterator<K,V>(this); |
2728 |
dl |
1.1 |
} |
2729 |
|
|
|
2730 |
|
|
/** |
2731 |
dl |
1.41 |
* 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 |
dl |
1.2 |
* 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()}. |
2761 |
|
|
* |
2762 |
|
|
* @return the hash code value for this map |
2763 |
dl |
1.1 |
*/ |
2764 |
|
|
public int hashCode() { |
2765 |
dl |
1.14 |
int h = 0; |
2766 |
dl |
1.41 |
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 |
dl |
1.14 |
} |
2771 |
|
|
return h; |
2772 |
dl |
1.1 |
} |
2773 |
|
|
|
2774 |
|
|
/** |
2775 |
dl |
1.2 |
* Returns a string representation of this map. The string |
2776 |
|
|
* representation consists of a list of key-value mappings (in no |
2777 |
|
|
* particular order) enclosed in braces ("{@code {}}"). Adjacent |
2778 |
|
|
* mappings are separated by the characters {@code ", "} (comma |
2779 |
|
|
* and space). Each key-value mapping is rendered as the key |
2780 |
|
|
* followed by an equals sign ("{@code =}") followed by the |
2781 |
|
|
* associated value. |
2782 |
|
|
* |
2783 |
|
|
* @return a string representation of this map |
2784 |
dl |
1.1 |
*/ |
2785 |
|
|
public String toString() { |
2786 |
dl |
1.41 |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
2787 |
dl |
1.14 |
StringBuilder sb = new StringBuilder(); |
2788 |
|
|
sb.append('{'); |
2789 |
dl |
1.41 |
Object v; |
2790 |
|
|
if ((v = it.advance()) != null) { |
2791 |
dl |
1.14 |
for (;;) { |
2792 |
dl |
1.41 |
Object k = it.nextKey; |
2793 |
dl |
1.14 |
sb.append(k == this ? "(this Map)" : k); |
2794 |
|
|
sb.append('='); |
2795 |
|
|
sb.append(v == this ? "(this Map)" : v); |
2796 |
dl |
1.41 |
if ((v = it.advance()) == null) |
2797 |
dl |
1.14 |
break; |
2798 |
|
|
sb.append(',').append(' '); |
2799 |
|
|
} |
2800 |
|
|
} |
2801 |
|
|
return sb.append('}').toString(); |
2802 |
dl |
1.1 |
} |
2803 |
|
|
|
2804 |
|
|
/** |
2805 |
dl |
1.2 |
* Compares the specified object with this map for equality. |
2806 |
|
|
* Returns {@code true} if the given object is a map with the same |
2807 |
|
|
* mappings as this map. This operation may return misleading |
2808 |
|
|
* results if either map is concurrently modified during execution |
2809 |
|
|
* of this method. |
2810 |
|
|
* |
2811 |
|
|
* @param o object to be compared for equality with this map |
2812 |
|
|
* @return {@code true} if the specified object is equal to this map |
2813 |
dl |
1.1 |
*/ |
2814 |
|
|
public boolean equals(Object o) { |
2815 |
dl |
1.14 |
if (o != this) { |
2816 |
|
|
if (!(o instanceof Map)) |
2817 |
|
|
return false; |
2818 |
|
|
Map<?,?> m = (Map<?,?>) o; |
2819 |
dl |
1.41 |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
2820 |
|
|
Object val; |
2821 |
|
|
while ((val = it.advance()) != null) { |
2822 |
dl |
1.14 |
Object v = m.get(it.nextKey); |
2823 |
|
|
if (v == null || (v != val && !v.equals(val))) |
2824 |
dl |
1.1 |
return false; |
2825 |
dl |
1.14 |
} |
2826 |
dl |
1.1 |
for (Map.Entry<?,?> e : m.entrySet()) { |
2827 |
dl |
1.14 |
Object mk, mv, v; |
2828 |
|
|
if ((mk = e.getKey()) == null || |
2829 |
|
|
(mv = e.getValue()) == null || |
2830 |
|
|
(v = internalGet(mk)) == null || |
2831 |
|
|
(mv != v && !mv.equals(v))) |
2832 |
dl |
1.1 |
return false; |
2833 |
|
|
} |
2834 |
dl |
1.14 |
} |
2835 |
|
|
return true; |
2836 |
|
|
} |
2837 |
|
|
|
2838 |
|
|
/* ----------------Iterators -------------- */ |
2839 |
|
|
|
2840 |
dl |
1.41 |
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 |
|
|
public KeyIterator<K,V> split() { |
2847 |
|
|
if (last != null || (next != null && nextVal == null)) |
2848 |
|
|
throw new IllegalStateException(); |
2849 |
|
|
return new KeyIterator<K,V>(this, true); |
2850 |
dl |
1.14 |
} |
2851 |
dl |
1.41 |
public KeyIterator<K,V> clone() { |
2852 |
|
|
if (last != null || (next != null && nextVal == null)) |
2853 |
dl |
1.14 |
throw new IllegalStateException(); |
2854 |
dl |
1.41 |
return new KeyIterator<K,V>(this, false); |
2855 |
dl |
1.14 |
} |
2856 |
|
|
|
2857 |
|
|
@SuppressWarnings("unchecked") |
2858 |
|
|
public final K next() { |
2859 |
dl |
1.41 |
if (nextVal == null && advance() == null) |
2860 |
dl |
1.14 |
throw new NoSuchElementException(); |
2861 |
|
|
Object k = nextKey; |
2862 |
dl |
1.41 |
nextVal = null; |
2863 |
|
|
return (K) k; |
2864 |
dl |
1.14 |
} |
2865 |
|
|
|
2866 |
|
|
public final K nextElement() { return next(); } |
2867 |
|
|
} |
2868 |
|
|
|
2869 |
dl |
1.41 |
static final class ValueIterator<K,V> extends InternalIterator<K,V> |
2870 |
|
|
implements Spliterator<V>, Enumeration<V> { |
2871 |
dl |
1.14 |
ValueIterator(ConcurrentHashMapV8<K, V> map) { super(map); } |
2872 |
dl |
1.41 |
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 |
dl |
1.14 |
|
2887 |
|
|
@SuppressWarnings("unchecked") |
2888 |
|
|
public final V next() { |
2889 |
dl |
1.41 |
Object v; |
2890 |
|
|
if ((v = nextVal) == null && (v = advance()) == null) |
2891 |
dl |
1.14 |
throw new NoSuchElementException(); |
2892 |
dl |
1.41 |
nextVal = null; |
2893 |
|
|
return (V) v; |
2894 |
dl |
1.14 |
} |
2895 |
|
|
|
2896 |
|
|
public final V nextElement() { return next(); } |
2897 |
|
|
} |
2898 |
|
|
|
2899 |
dl |
1.41 |
static final class EntryIterator<K,V> extends InternalIterator<K,V> |
2900 |
|
|
implements Spliterator<Map.Entry<K,V>> { |
2901 |
dl |
1.14 |
EntryIterator(ConcurrentHashMapV8<K, V> map) { super(map); } |
2902 |
dl |
1.41 |
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 |
dl |
1.24 |
} |
2915 |
|
|
|
2916 |
|
|
@SuppressWarnings("unchecked") |
2917 |
|
|
public final Map.Entry<K,V> next() { |
2918 |
dl |
1.41 |
Object v; |
2919 |
|
|
if ((v = nextVal) == null && (v = advance()) == null) |
2920 |
dl |
1.24 |
throw new NoSuchElementException(); |
2921 |
|
|
Object k = nextKey; |
2922 |
dl |
1.41 |
nextVal = null; |
2923 |
|
|
return new MapEntry<K,V>((K)k, (V)v, map); |
2924 |
dl |
1.1 |
} |
2925 |
|
|
} |
2926 |
|
|
|
2927 |
|
|
/** |
2928 |
dl |
1.41 |
* Exported Entry for iterators |
2929 |
dl |
1.1 |
*/ |
2930 |
dl |
1.41 |
static final class MapEntry<K,V> implements Map.Entry<K, V> { |
2931 |
dl |
1.14 |
final K key; // non-null |
2932 |
|
|
V val; // non-null |
2933 |
dl |
1.41 |
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 |
|
|
} |
2939 |
dl |
1.14 |
public final K getKey() { return key; } |
2940 |
|
|
public final V getValue() { return val; } |
2941 |
|
|
public final int hashCode() { return key.hashCode() ^ val.hashCode(); } |
2942 |
|
|
public final String toString(){ return key + "=" + val; } |
2943 |
|
|
|
2944 |
|
|
public final boolean equals(Object o) { |
2945 |
|
|
Object k, v; Map.Entry<?,?> e; |
2946 |
|
|
return ((o instanceof Map.Entry) && |
2947 |
|
|
(k = (e = (Map.Entry<?,?>)o).getKey()) != null && |
2948 |
|
|
(v = e.getValue()) != null && |
2949 |
|
|
(k == key || k.equals(key)) && |
2950 |
|
|
(v == val || v.equals(val))); |
2951 |
dl |
1.1 |
} |
2952 |
|
|
|
2953 |
|
|
/** |
2954 |
|
|
* Sets our entry's value and writes through to the map. The |
2955 |
dl |
1.41 |
* 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 |
dl |
1.1 |
*/ |
2961 |
dl |
1.14 |
public final V setValue(V value) { |
2962 |
dl |
1.1 |
if (value == null) throw new NullPointerException(); |
2963 |
dl |
1.14 |
V v = val; |
2964 |
|
|
val = value; |
2965 |
|
|
map.put(key, value); |
2966 |
dl |
1.1 |
return v; |
2967 |
|
|
} |
2968 |
|
|
} |
2969 |
|
|
|
2970 |
dl |
1.14 |
/* ----------------Views -------------- */ |
2971 |
dl |
1.1 |
|
2972 |
dl |
1.24 |
/** |
2973 |
dl |
1.41 |
* Base class for views. |
2974 |
dl |
1.14 |
*/ |
2975 |
dl |
1.24 |
static abstract class MapView<K, V> { |
2976 |
dl |
1.14 |
final ConcurrentHashMapV8<K, V> map; |
2977 |
dl |
1.24 |
MapView(ConcurrentHashMapV8<K, V> map) { this.map = map; } |
2978 |
dl |
1.14 |
public final int size() { return map.size(); } |
2979 |
|
|
public final boolean isEmpty() { return map.isEmpty(); } |
2980 |
|
|
public final void clear() { map.clear(); } |
2981 |
dl |
1.24 |
|
2982 |
|
|
// implementations below rely on concrete classes supplying these |
2983 |
dl |
1.41 |
abstract public Iterator<?> iterator(); |
2984 |
dl |
1.24 |
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 |
dl |
1.41 |
Iterator<?> it = iterator(); |
2997 |
dl |
1.24 |
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 |
dl |
1.41 |
Iterator<?> it = iterator(); |
3024 |
dl |
1.24 |
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 |
dl |
1.41 |
for (Iterator<?> it = iterator(); it.hasNext();) |
3046 |
dl |
1.24 |
h += it.next().hashCode(); |
3047 |
|
|
return h; |
3048 |
|
|
} |
3049 |
|
|
|
3050 |
|
|
public final String toString() { |
3051 |
|
|
StringBuilder sb = new StringBuilder(); |
3052 |
|
|
sb.append('['); |
3053 |
dl |
1.41 |
Iterator<?> it = iterator(); |
3054 |
dl |
1.24 |
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 |
jsr166 |
1.32 |
public final boolean removeAll(Collection<?> c) { |
3078 |
dl |
1.24 |
boolean modified = false; |
3079 |
dl |
1.41 |
for (Iterator<?> it = iterator(); it.hasNext();) { |
3080 |
dl |
1.24 |
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 |
dl |
1.41 |
for (Iterator<?> it = iterator(); it.hasNext();) { |
3091 |
dl |
1.24 |
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 |
dl |
1.14 |
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 |
dl |
1.1 |
} |
3108 |
dl |
1.24 |
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 |
dl |
1.1 |
} |
3121 |
|
|
|
3122 |
dl |
1.24 |
static final class Values<K,V> extends MapView<K,V> |
3123 |
jsr166 |
1.34 |
implements Collection<V> { |
3124 |
dl |
1.24 |
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 |
dl |
1.14 |
public final Iterator<V> iterator() { |
3139 |
|
|
return new ValueIterator<K,V>(map); |
3140 |
dl |
1.1 |
} |
3141 |
dl |
1.24 |
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 |
dl |
1.1 |
} |
3148 |
|
|
|
3149 |
jsr166 |
1.33 |
static final class EntrySet<K,V> extends MapView<K,V> |
3150 |
dl |
1.24 |
implements Set<Map.Entry<K,V>> { |
3151 |
|
|
EntrySet(ConcurrentHashMapV8<K, V> map) { super(map); } |
3152 |
dl |
1.14 |
public final boolean contains(Object o) { |
3153 |
|
|
Object k, v, r; Map.Entry<?,?> e; |
3154 |
|
|
return ((o instanceof Map.Entry) && |
3155 |
|
|
(k = (e = (Map.Entry<?,?>)o).getKey()) != null && |
3156 |
|
|
(r = map.get(k)) != null && |
3157 |
|
|
(v = e.getValue()) != null && |
3158 |
|
|
(v == r || v.equals(r))); |
3159 |
dl |
1.1 |
} |
3160 |
dl |
1.14 |
public final boolean remove(Object o) { |
3161 |
|
|
Object k, v; Map.Entry<?,?> e; |
3162 |
|
|
return ((o instanceof Map.Entry) && |
3163 |
|
|
(k = (e = (Map.Entry<?,?>)o).getKey()) != null && |
3164 |
|
|
(v = e.getValue()) != null && |
3165 |
|
|
map.remove(k, v)); |
3166 |
dl |
1.1 |
} |
3167 |
dl |
1.24 |
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 |
dl |
1.1 |
} |
3183 |
|
|
|
3184 |
|
|
/* ---------------- Serialization Support -------------- */ |
3185 |
|
|
|
3186 |
|
|
/** |
3187 |
dl |
1.14 |
* Stripped-down version of helper class used in previous version, |
3188 |
|
|
* declared for the sake of serialization compatibility |
3189 |
dl |
1.1 |
*/ |
3190 |
dl |
1.14 |
static class Segment<K,V> implements Serializable { |
3191 |
dl |
1.1 |
private static final long serialVersionUID = 2249069246763182397L; |
3192 |
|
|
final float loadFactor; |
3193 |
|
|
Segment(float lf) { this.loadFactor = lf; } |
3194 |
|
|
} |
3195 |
|
|
|
3196 |
|
|
/** |
3197 |
|
|
* Saves the state of the {@code ConcurrentHashMapV8} instance to a |
3198 |
|
|
* stream (i.e., serializes it). |
3199 |
|
|
* @param s the stream |
3200 |
|
|
* @serialData |
3201 |
|
|
* the key (Object) and value (Object) |
3202 |
|
|
* for each key-value mapping, followed by a null pair. |
3203 |
|
|
* The key-value mappings are emitted in no particular order. |
3204 |
|
|
*/ |
3205 |
|
|
@SuppressWarnings("unchecked") |
3206 |
|
|
private void writeObject(java.io.ObjectOutputStream s) |
3207 |
|
|
throws java.io.IOException { |
3208 |
|
|
if (segments == null) { // for serialization compatibility |
3209 |
|
|
segments = (Segment<K,V>[]) |
3210 |
|
|
new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL]; |
3211 |
|
|
for (int i = 0; i < segments.length; ++i) |
3212 |
dl |
1.16 |
segments[i] = new Segment<K,V>(LOAD_FACTOR); |
3213 |
dl |
1.1 |
} |
3214 |
|
|
s.defaultWriteObject(); |
3215 |
dl |
1.41 |
InternalIterator<K,V> it = new InternalIterator<K,V>(this); |
3216 |
|
|
Object v; |
3217 |
|
|
while ((v = it.advance()) != null) { |
3218 |
dl |
1.14 |
s.writeObject(it.nextKey); |
3219 |
dl |
1.41 |
s.writeObject(v); |
3220 |
dl |
1.14 |
} |
3221 |
dl |
1.1 |
s.writeObject(null); |
3222 |
|
|
s.writeObject(null); |
3223 |
|
|
segments = null; // throw away |
3224 |
|
|
} |
3225 |
|
|
|
3226 |
|
|
/** |
3227 |
jsr166 |
1.9 |
* Reconstitutes the instance from a stream (that is, deserializes it). |
3228 |
dl |
1.1 |
* @param s the stream |
3229 |
|
|
*/ |
3230 |
|
|
@SuppressWarnings("unchecked") |
3231 |
|
|
private void readObject(java.io.ObjectInputStream s) |
3232 |
|
|
throws java.io.IOException, ClassNotFoundException { |
3233 |
|
|
s.defaultReadObject(); |
3234 |
|
|
this.segments = null; // unneeded |
3235 |
jsr166 |
1.21 |
// initialize transient final field |
3236 |
dl |
1.14 |
UNSAFE.putObjectVolatile(this, counterOffset, new LongAdder()); |
3237 |
|
|
|
3238 |
|
|
// Create all nodes, then place in table once size is known |
3239 |
|
|
long size = 0L; |
3240 |
|
|
Node p = null; |
3241 |
dl |
1.1 |
for (;;) { |
3242 |
dl |
1.14 |
K k = (K) s.readObject(); |
3243 |
|
|
V v = (V) s.readObject(); |
3244 |
|
|
if (k != null && v != null) { |
3245 |
dl |
1.38 |
int h = spread(k.hashCode()); |
3246 |
|
|
p = new Node(h, k, v, p); |
3247 |
dl |
1.14 |
++size; |
3248 |
|
|
} |
3249 |
|
|
else |
3250 |
dl |
1.1 |
break; |
3251 |
dl |
1.14 |
} |
3252 |
|
|
if (p != null) { |
3253 |
|
|
boolean init = false; |
3254 |
dl |
1.24 |
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 |
dl |
1.38 |
boolean collide = false; |
3263 |
dl |
1.24 |
if (n > sc && |
3264 |
|
|
UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) { |
3265 |
dl |
1.14 |
try { |
3266 |
|
|
if (table == null) { |
3267 |
|
|
init = true; |
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 |
dl |
1.38 |
Node q = p.next = tabAt(tab, j); |
3274 |
dl |
1.14 |
setTabAt(tab, j, p); |
3275 |
dl |
1.38 |
if (!collide && q != null && q.hash == p.hash) |
3276 |
|
|
collide = true; |
3277 |
dl |
1.14 |
p = next; |
3278 |
|
|
} |
3279 |
|
|
table = tab; |
3280 |
|
|
counter.add(size); |
3281 |
dl |
1.29 |
sc = n - (n >>> 2); |
3282 |
dl |
1.14 |
} |
3283 |
|
|
} finally { |
3284 |
dl |
1.24 |
sizeCtl = sc; |
3285 |
dl |
1.14 |
} |
3286 |
dl |
1.38 |
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 |
dl |
1.14 |
} |
3300 |
|
|
if (!init) { // Can only happen if unsafely published. |
3301 |
|
|
while (p != null) { |
3302 |
dl |
1.27 |
internalPut(p.key, p.val); |
3303 |
dl |
1.14 |
p = p.next; |
3304 |
|
|
} |
3305 |
|
|
} |
3306 |
dl |
1.1 |
} |
3307 |
|
|
} |
3308 |
|
|
|
3309 |
|
|
// Unsafe mechanics |
3310 |
|
|
private static final sun.misc.Unsafe UNSAFE; |
3311 |
|
|
private static final long counterOffset; |
3312 |
dl |
1.24 |
private static final long sizeCtlOffset; |
3313 |
dl |
1.1 |
private static final long ABASE; |
3314 |
|
|
private static final int ASHIFT; |
3315 |
|
|
|
3316 |
|
|
static { |
3317 |
|
|
int ss; |
3318 |
|
|
try { |
3319 |
|
|
UNSAFE = getUnsafe(); |
3320 |
|
|
Class<?> k = ConcurrentHashMapV8.class; |
3321 |
|
|
counterOffset = UNSAFE.objectFieldOffset |
3322 |
|
|
(k.getDeclaredField("counter")); |
3323 |
dl |
1.24 |
sizeCtlOffset = UNSAFE.objectFieldOffset |
3324 |
|
|
(k.getDeclaredField("sizeCtl")); |
3325 |
dl |
1.1 |
Class<?> sc = Node[].class; |
3326 |
|
|
ABASE = UNSAFE.arrayBaseOffset(sc); |
3327 |
|
|
ss = UNSAFE.arrayIndexScale(sc); |
3328 |
|
|
} catch (Exception e) { |
3329 |
|
|
throw new Error(e); |
3330 |
|
|
} |
3331 |
|
|
if ((ss & (ss-1)) != 0) |
3332 |
|
|
throw new Error("data type scale not a power of two"); |
3333 |
|
|
ASHIFT = 31 - Integer.numberOfLeadingZeros(ss); |
3334 |
|
|
} |
3335 |
|
|
|
3336 |
|
|
/** |
3337 |
|
|
* Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package. |
3338 |
|
|
* Replace with a simple call to Unsafe.getUnsafe when integrating |
3339 |
|
|
* into a jdk. |
3340 |
|
|
* |
3341 |
|
|
* @return a sun.misc.Unsafe |
3342 |
|
|
*/ |
3343 |
|
|
private static sun.misc.Unsafe getUnsafe() { |
3344 |
|
|
try { |
3345 |
|
|
return sun.misc.Unsafe.getUnsafe(); |
3346 |
|
|
} catch (SecurityException se) { |
3347 |
|
|
try { |
3348 |
|
|
return java.security.AccessController.doPrivileged |
3349 |
|
|
(new java.security |
3350 |
|
|
.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
3351 |
|
|
public sun.misc.Unsafe run() throws Exception { |
3352 |
|
|
java.lang.reflect.Field f = sun.misc |
3353 |
|
|
.Unsafe.class.getDeclaredField("theUnsafe"); |
3354 |
|
|
f.setAccessible(true); |
3355 |
|
|
return (sun.misc.Unsafe) f.get(null); |
3356 |
|
|
}}); |
3357 |
|
|
} catch (java.security.PrivilegedActionException e) { |
3358 |
|
|
throw new RuntimeException("Could not initialize intrinsics", |
3359 |
|
|
e.getCause()); |
3360 |
|
|
} |
3361 |
|
|
} |
3362 |
|
|
} |
3363 |
|
|
|
3364 |
|
|
} |