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/* |
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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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|
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package jsr166e.extra; |
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import jsr166e.*; |
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import java.util.*; |
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|
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/** |
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* A class with the same methods and array-based characteristics as |
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* {@link java.util.Vector} but with reduced contention and improved |
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* throughput when invocations of read-only methods by multiple |
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* threads are most common. |
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* |
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* <p> The iterators returned by this class's {@link #iterator() |
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* iterator} and {@link #listIterator(int) listIterator} methods are |
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* best-effort in the presence of concurrent modifications, and do |
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* <em>NOT</em> throw {@link ConcurrentModificationException}. An |
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* iterator's {@code next()} method returns consecutive elements as |
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* they appear in the underlying array upon each access. Alternatively, |
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* method {@link #snapshotIterator} may be used for deterministic |
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* traversals, at the expense of making a copy, and unavailability of |
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* method {@code Iterator.remove}. |
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* |
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* <p>Otherwise, this class supports all methods, under the same |
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* documented specifications, as {@code Vector}. Consult {@link |
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* java.util.Vector} for detailed specifications. Additionally, this |
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* class provides methods {@link #addIfAbsent} and {@link |
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* #addAllAbsent}. |
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* |
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* @author Doug Lea |
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*/ |
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public class ReadMostlyVector<E> |
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implements List<E>, RandomAccess, Cloneable, java.io.Serializable { |
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private static final long serialVersionUID = 8673264195747942595L; |
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|
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/* |
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* This class exists mainly as a vehicle to exercise various |
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* constructions using SequenceLocks. Read-only methods |
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* take one of a few forms: |
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* |
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* Short methods,including get(index), continually retry obtaining |
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* a snapshot of array, count, and element, using sequence number |
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* to validate. |
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* |
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* Methods that are potentially O(n) (or worse) try once in |
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* read-only mode, and then lock. When in read-only mode, they |
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* validate only at the end of an array scan unless the element is |
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* actually used (for example, as an argument of method equals). |
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*/ |
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|
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/** |
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* The maximum size of array to allocate. |
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* See CopyOnWriteArrayList for explanation. |
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*/ |
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private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; |
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|
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// fields are non-private to simpify nested class access |
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volatile Object[] array; |
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final SequenceLock lock; |
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volatile int count; |
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final int capacityIncrement; |
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|
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/** |
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* Creates an empty vector with the given initial capacity and |
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* capacity increment. |
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* |
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* @param initialCapacity the initial capacity of the underlying array |
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* @param capacityIncrement if non-zero, the number to |
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* add when resizing to accommodate additional elements. |
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* If zero, the array size is doubled when resized. |
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* |
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* @throws IllegalArgumentException if initial capacity is negative |
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*/ |
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public ReadMostlyVector(int initialCapacity, int capacityIncrement) { |
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super(); |
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if (initialCapacity < 0) |
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throw new IllegalArgumentException("Illegal Capacity: "+ |
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initialCapacity); |
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this.array = new Object[initialCapacity]; |
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this.capacityIncrement = capacityIncrement; |
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this.lock = new SequenceLock(); |
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} |
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|
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/** |
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* Creates an empty vector with the given initial capacity. |
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* |
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* @param initialCapacity the initial capacity of the underlying array |
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* |
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* @throws IllegalArgumentException if initial capacity is negative |
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*/ |
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public ReadMostlyVector(int initialCapacity) { |
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this(initialCapacity, 0); |
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} |
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|
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/** |
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* Creates an empty vector with an underlying array of size {@code 10}. |
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*/ |
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public ReadMostlyVector() { |
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this(10, 0); |
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} |
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|
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/** |
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* Creates a vector containing the elements of the specified |
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* collection, in the order they are returned by the collection's |
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* iterator. |
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* |
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* @param c the collection of initially held elements |
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* @throws NullPointerException if the specified collection is null |
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*/ |
113 |
public ReadMostlyVector(Collection<? extends E> c) { |
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Object[] elements = c.toArray(); |
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// c.toArray might (incorrectly) not return Object[] (see 6260652) |
116 |
if (elements.getClass() != Object[].class) |
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elements = Arrays.copyOf(elements, elements.length, Object[].class); |
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this.array = elements; |
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this.count = elements.length; |
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this.capacityIncrement = 0; |
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this.lock = new SequenceLock(); |
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} |
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|
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// internal constructor for clone |
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ReadMostlyVector(Object[] array, int count, int capacityIncrement) { |
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this.array = array; |
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this.count = count; |
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this.capacityIncrement = capacityIncrement; |
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this.lock = new SequenceLock(); |
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} |
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|
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// For explanation, see CopyOnWriteArrayList |
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final Object[] grow(int minCapacity) { |
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int oldCapacity = array.length; |
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int newCapacity = oldCapacity + ((capacityIncrement > 0) ? |
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capacityIncrement : oldCapacity); |
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if (newCapacity - minCapacity < 0) |
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newCapacity = minCapacity; |
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if (newCapacity - MAX_ARRAY_SIZE > 0) |
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newCapacity = hugeCapacity(minCapacity); |
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return array = Arrays.copyOf(array, newCapacity); |
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} |
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|
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static int hugeCapacity(int minCapacity) { |
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if (minCapacity < 0) // overflow |
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throw new OutOfMemoryError(); |
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return (minCapacity > MAX_ARRAY_SIZE) ? |
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Integer.MAX_VALUE : |
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MAX_ARRAY_SIZE; |
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} |
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|
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/* |
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* Internal versions of most base functionality, wrapped |
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* in different ways from public methods from this class |
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* as well as sublist and iterator classes. |
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*/ |
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|
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// Version of indexOf that returns -1 if either not present or invalid |
159 |
final int validatedIndexOf(Object x, Object[] items, int index, int fence, |
160 |
long seq) { |
161 |
for (int i = index; i < fence; ++i) { |
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Object e = items[i]; |
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if (lock.getSequence() != seq) |
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break; |
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if ((x == null) ? e == null : x.equals(e)) |
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return i; |
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} |
168 |
return -1; |
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} |
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|
171 |
final int rawIndexOf(Object x, int index, int fence) { |
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Object[] items = array; |
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for (int i = index; i < fence; ++i) { |
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Object e = items[i]; |
175 |
if ((x == null) ? e == null : x.equals(e)) |
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return i; |
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} |
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return -1; |
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} |
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|
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final int validatedLastIndexOf(Object x, Object[] items, |
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int index, int origin, long seq) { |
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for (int i = index; i >= origin; --i) { |
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Object e = items[i]; |
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if (lock.getSequence() != seq) |
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break; |
187 |
if ((x == null) ? e == null : x.equals(e)) |
188 |
return i; |
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} |
190 |
return -1; |
191 |
} |
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|
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final int rawLastIndexOf(Object x, int index, int origin) { |
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Object[] items = array; |
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for (int i = index; i >= origin; --i) { |
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Object e = items[i]; |
197 |
if ((x == null) ? e == null : x.equals(e)) |
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return i; |
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} |
200 |
return -1; |
201 |
} |
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|
203 |
final void rawAdd(E e) { |
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int n = count; |
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Object[] items = array; |
206 |
if (n >= items.length) |
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items = grow(n + 1); |
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items[n] = e; |
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count = n + 1; |
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} |
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|
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final void rawAddAt(int index, E e) { |
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int n = count; |
214 |
Object[] items = array; |
215 |
if (index > n) |
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throw new ArrayIndexOutOfBoundsException(index); |
217 |
if (n >= items.length) |
218 |
items = grow(n + 1); |
219 |
if (index < n) |
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System.arraycopy(items, index, items, index + 1, n - index); |
221 |
items[index] = e; |
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count = n + 1; |
223 |
} |
224 |
|
225 |
final boolean rawAddAllAt(int index, Object[] elements) { |
226 |
int n = count; |
227 |
Object[] items = array; |
228 |
if (index < 0 || index > n) |
229 |
throw new ArrayIndexOutOfBoundsException(index); |
230 |
int len = elements.length; |
231 |
if (len == 0) |
232 |
return false; |
233 |
int newCount = n + len; |
234 |
if (newCount >= items.length) |
235 |
items = grow(newCount); |
236 |
int mv = n - index; |
237 |
if (mv > 0) |
238 |
System.arraycopy(items, index, items, index + len, mv); |
239 |
System.arraycopy(elements, 0, items, index, len); |
240 |
count = newCount; |
241 |
return true; |
242 |
} |
243 |
|
244 |
final boolean rawRemoveAt(int index) { |
245 |
int n = count - 1; |
246 |
Object[] items = array; |
247 |
if (index < 0 || index > n) |
248 |
return false; |
249 |
int mv = n - index; |
250 |
if (mv > 0) |
251 |
System.arraycopy(items, index + 1, items, index, mv); |
252 |
items[n] = null; |
253 |
count = n; |
254 |
return true; |
255 |
} |
256 |
|
257 |
/** |
258 |
* Internal version of removeAll for lists and sublists. In this |
259 |
* and other similar methods below, the bound argument is, if |
260 |
* non-negative, the purported upper bound of a list/sublist, or |
261 |
* is left negative if the bound should be determined via count |
262 |
* field under lock. |
263 |
*/ |
264 |
final boolean internalRemoveAll(Collection<?> c, int origin, int bound) { |
265 |
final SequenceLock lock = this.lock; |
266 |
boolean removed = false; |
267 |
lock.lock(); |
268 |
try { |
269 |
int n = count; |
270 |
int fence = bound < 0 || bound > n ? n : bound; |
271 |
if (origin >= 0 && origin < fence) { |
272 |
for (Object x : c) { |
273 |
while (rawRemoveAt(rawIndexOf(x, origin, fence))) |
274 |
removed = true; |
275 |
} |
276 |
} |
277 |
} finally { |
278 |
lock.unlock(); |
279 |
} |
280 |
return removed; |
281 |
} |
282 |
|
283 |
final boolean internalRetainAll(Collection<?> c, int origin, int bound) { |
284 |
final SequenceLock lock = this.lock; |
285 |
boolean removed = false; |
286 |
if (c != this) { |
287 |
lock.lock(); |
288 |
try { |
289 |
Object[] items = array; |
290 |
int i = origin; |
291 |
int n = count; |
292 |
int fence = bound < 0 || bound > n ? n : bound; |
293 |
while (i >= 0 && i < fence) { |
294 |
if (c.contains(items[i])) |
295 |
++i; |
296 |
else { |
297 |
--fence; |
298 |
int mv = --n - i; |
299 |
if (mv > 0) |
300 |
System.arraycopy(items, i + 1, items, i, mv); |
301 |
} |
302 |
} |
303 |
if (count != n) { |
304 |
count = n; |
305 |
removed = true; |
306 |
} |
307 |
} finally { |
308 |
lock.unlock(); |
309 |
} |
310 |
} |
311 |
return removed; |
312 |
} |
313 |
|
314 |
final void internalClear(int origin, int bound) { |
315 |
int n = count; |
316 |
int fence = bound < 0 || bound > n ? n : bound; |
317 |
if (origin >= 0 && origin < fence) { |
318 |
Object[] items = array; |
319 |
int removed = fence - origin; |
320 |
int newCount = n - removed; |
321 |
int mv = n - (origin + removed); |
322 |
if (mv > 0) |
323 |
System.arraycopy(items, origin + removed, items, origin, mv); |
324 |
for (int i = n; i < newCount; ++i) |
325 |
items[i] = null; |
326 |
count = newCount; |
327 |
} |
328 |
} |
329 |
|
330 |
final boolean internalContainsAll(Collection<?> c, int origin, int bound) { |
331 |
final SequenceLock lock = this.lock; |
332 |
boolean contained; |
333 |
boolean locked = false; |
334 |
try { |
335 |
for (;;) { |
336 |
long seq = lock.awaitAvailability(); |
337 |
int n = count; |
338 |
Object[] items = array; |
339 |
int len = items.length; |
340 |
if (n > len) |
341 |
continue; |
342 |
int fence = bound < 0 || bound > n ? n : bound; |
343 |
if (origin < 0) |
344 |
contained = false; |
345 |
else { |
346 |
contained = true; |
347 |
for (Object e : c) { |
348 |
int idx = (locked ? |
349 |
rawIndexOf(e, origin, fence) : |
350 |
validatedIndexOf(e, items, origin, |
351 |
fence, seq)); |
352 |
if (idx < 0) { |
353 |
contained = false; |
354 |
break; |
355 |
} |
356 |
} |
357 |
} |
358 |
if (lock.getSequence() == seq) |
359 |
break; |
360 |
lock.lock(); |
361 |
locked = true; |
362 |
} |
363 |
} finally { |
364 |
if (locked) |
365 |
lock.unlock(); |
366 |
} |
367 |
return contained; |
368 |
} |
369 |
|
370 |
final boolean internalEquals(List<?> list, int origin, int bound) { |
371 |
final SequenceLock lock = this.lock; |
372 |
boolean locked = false; |
373 |
boolean equal; |
374 |
try { |
375 |
for (;;) { |
376 |
long seq = lock.awaitAvailability(); |
377 |
Object[] items = array; |
378 |
int n = count; |
379 |
if (n > items.length || origin < 0) |
380 |
equal = false; |
381 |
else { |
382 |
equal = true; |
383 |
int fence = bound < 0 || bound > n ? n : bound; |
384 |
Iterator<?> it = list.iterator(); |
385 |
for (int i = origin; i < fence; ++i) { |
386 |
Object x = items[i]; |
387 |
Object y; |
388 |
if ((!locked && lock.getSequence() != seq) || |
389 |
!it.hasNext() || |
390 |
(y = it.next()) == null ? |
391 |
x != null : !y.equals(x)) { |
392 |
equal = false; |
393 |
break; |
394 |
} |
395 |
} |
396 |
if (equal && it.hasNext()) |
397 |
equal = false; |
398 |
} |
399 |
if (lock.getSequence() == seq) |
400 |
break; |
401 |
lock.lock(); |
402 |
locked = true; |
403 |
} |
404 |
} finally { |
405 |
if (locked) |
406 |
lock.unlock(); |
407 |
} |
408 |
return equal; |
409 |
} |
410 |
|
411 |
final int internalHashCode(int origin, int bound) { |
412 |
final SequenceLock lock = this.lock; |
413 |
int hash; |
414 |
boolean locked = false; |
415 |
try { |
416 |
for (;;) { |
417 |
hash = 1; |
418 |
long seq = lock.awaitAvailability(); |
419 |
Object[] items = array; |
420 |
int n = count; |
421 |
int len = items.length; |
422 |
if (n > len) |
423 |
continue; |
424 |
int fence = bound < 0 || bound > n ? n : bound; |
425 |
if (origin >= 0) { |
426 |
for (int i = origin; i < fence; ++i) { |
427 |
Object e = items[i]; |
428 |
hash = 31*hash + (e == null ? 0 : e.hashCode()); |
429 |
} |
430 |
} |
431 |
if (lock.getSequence() == seq) |
432 |
break; |
433 |
lock.lock(); |
434 |
locked = true; |
435 |
} |
436 |
} finally { |
437 |
if (locked) |
438 |
lock.unlock(); |
439 |
} |
440 |
return hash; |
441 |
} |
442 |
|
443 |
final String internalToString(int origin, int bound) { |
444 |
final SequenceLock lock = this.lock; |
445 |
String ret; |
446 |
boolean locked = false; |
447 |
try { |
448 |
outer:for (;;) { |
449 |
long seq = lock.awaitAvailability(); |
450 |
Object[] items = array; |
451 |
int n = count; |
452 |
int len = items.length; |
453 |
if (n > len) |
454 |
continue; |
455 |
int fence = bound < 0 || bound > n ? n : bound; |
456 |
if (origin < 0 || origin == fence) |
457 |
ret = "[]"; |
458 |
else { |
459 |
StringBuilder sb = new StringBuilder(); |
460 |
sb.append('['); |
461 |
for (int i = origin;;) { |
462 |
Object e = items[i]; |
463 |
if (e == this) |
464 |
sb.append("(this Collection)"); |
465 |
else if (!locked && lock.getSequence() != seq) |
466 |
continue outer; |
467 |
else |
468 |
sb.append(e.toString()); |
469 |
if (++i < fence) |
470 |
sb.append(',').append(' '); |
471 |
else { |
472 |
ret = sb.append(']').toString(); |
473 |
break; |
474 |
} |
475 |
} |
476 |
} |
477 |
if (lock.getSequence() == seq) |
478 |
break; |
479 |
lock.lock(); |
480 |
locked = true; |
481 |
} |
482 |
} finally { |
483 |
if (locked) |
484 |
lock.unlock(); |
485 |
} |
486 |
return ret; |
487 |
} |
488 |
|
489 |
final Object[] internalToArray(int origin, int bound) { |
490 |
Object[] result; |
491 |
final SequenceLock lock = this.lock; |
492 |
boolean locked = false; |
493 |
try { |
494 |
for (;;) { |
495 |
result = null; |
496 |
long seq = lock.awaitAvailability(); |
497 |
Object[] items = array; |
498 |
int n = count; |
499 |
int len = items.length; |
500 |
if (n > len) |
501 |
continue; |
502 |
int fence = bound < 0 || bound > n ? n : bound; |
503 |
if (origin >= 0) |
504 |
result = Arrays.copyOfRange(items, origin, fence, |
505 |
Object[].class); |
506 |
if (lock.getSequence() == seq) |
507 |
break; |
508 |
lock.lock(); |
509 |
locked = true; |
510 |
} |
511 |
} finally { |
512 |
if (locked) |
513 |
lock.unlock(); |
514 |
} |
515 |
return result; |
516 |
} |
517 |
|
518 |
@SuppressWarnings("unchecked") |
519 |
final <T> T[] internalToArray(T[] a, int origin, int bound) { |
520 |
int alen = a.length; |
521 |
T[] result; |
522 |
final SequenceLock lock = this.lock; |
523 |
boolean locked = false; |
524 |
try { |
525 |
for (;;) { |
526 |
long seq = lock.awaitAvailability(); |
527 |
Object[] items = array; |
528 |
int n = count; |
529 |
int len = items.length; |
530 |
if (n > len) |
531 |
continue; |
532 |
int fence = bound < 0 || bound > n ? n : bound; |
533 |
int rlen = fence - origin; |
534 |
if (rlen < 0) |
535 |
rlen = 0; |
536 |
if (origin < 0 || alen >= rlen) { |
537 |
if (rlen > 0) |
538 |
System.arraycopy(items, 0, a, origin, rlen); |
539 |
if (alen > rlen) |
540 |
a[rlen] = null; |
541 |
result = a; |
542 |
} |
543 |
else |
544 |
result = (T[]) Arrays.copyOfRange(items, origin, |
545 |
fence, a.getClass()); |
546 |
if (lock.getSequence() == seq) |
547 |
break; |
548 |
lock.lock(); |
549 |
locked = true; |
550 |
} |
551 |
} finally { |
552 |
if (locked) |
553 |
lock.unlock(); |
554 |
} |
555 |
return result; |
556 |
} |
557 |
|
558 |
// public List methods |
559 |
|
560 |
public boolean add(E e) { |
561 |
final SequenceLock lock = this.lock; |
562 |
lock.lock(); |
563 |
try { |
564 |
rawAdd(e); |
565 |
} finally { |
566 |
lock.unlock(); |
567 |
} |
568 |
return true; |
569 |
} |
570 |
|
571 |
public void add(int index, E element) { |
572 |
final SequenceLock lock = this.lock; |
573 |
lock.lock(); |
574 |
try { |
575 |
rawAddAt(index, element); |
576 |
} finally { |
577 |
lock.unlock(); |
578 |
} |
579 |
} |
580 |
|
581 |
public boolean addAll(Collection<? extends E> c) { |
582 |
Object[] elements = c.toArray(); |
583 |
int len = elements.length; |
584 |
if (len == 0) |
585 |
return false; |
586 |
final SequenceLock lock = this.lock; |
587 |
lock.lock(); |
588 |
try { |
589 |
Object[] items = array; |
590 |
int n = count; |
591 |
int newCount = n + len; |
592 |
if (newCount >= items.length) |
593 |
items = grow(newCount); |
594 |
System.arraycopy(elements, 0, items, n, len); |
595 |
count = newCount; |
596 |
} finally { |
597 |
lock.unlock(); |
598 |
} |
599 |
return true; |
600 |
} |
601 |
|
602 |
public boolean addAll(int index, Collection<? extends E> c) { |
603 |
final SequenceLock lock = this.lock; |
604 |
boolean ret; |
605 |
Object[] elements = c.toArray(); |
606 |
lock.lock(); |
607 |
try { |
608 |
ret = rawAddAllAt(index, elements); |
609 |
} finally { |
610 |
lock.unlock(); |
611 |
} |
612 |
return ret; |
613 |
} |
614 |
|
615 |
public void clear() { |
616 |
final SequenceLock lock = this.lock; |
617 |
lock.lock(); |
618 |
try { |
619 |
int n = count; |
620 |
Object[] items = array; |
621 |
for (int i = 0; i < n; i++) |
622 |
items[i] = null; |
623 |
count = 0; |
624 |
} finally { |
625 |
lock.unlock(); |
626 |
} |
627 |
} |
628 |
|
629 |
public boolean contains(Object o) { |
630 |
return indexOf(o, 0) >= 0; |
631 |
} |
632 |
|
633 |
public boolean containsAll(Collection<?> c) { |
634 |
return internalContainsAll(c, 0, -1); |
635 |
} |
636 |
|
637 |
public boolean equals(Object o) { |
638 |
if (o == this) |
639 |
return true; |
640 |
if (!(o instanceof List)) |
641 |
return false; |
642 |
return internalEquals((List<?>)o, 0, -1); |
643 |
} |
644 |
|
645 |
public E get(int index) { |
646 |
final SequenceLock lock = this.lock; |
647 |
for (;;) { |
648 |
long seq = lock.awaitAvailability(); |
649 |
int n = count; |
650 |
Object[] items = array; |
651 |
if (n > items.length) |
652 |
continue; |
653 |
boolean outOfBounds = (index < 0 || index >= n); |
654 |
@SuppressWarnings("unchecked") |
655 |
E e = outOfBounds ? null : (E) items[index]; |
656 |
if (lock.getSequence() == seq) { |
657 |
if (outOfBounds) |
658 |
throw new ArrayIndexOutOfBoundsException(index); |
659 |
else |
660 |
return e; |
661 |
} |
662 |
} |
663 |
} |
664 |
|
665 |
public int hashCode() { |
666 |
return internalHashCode(0, -1); |
667 |
} |
668 |
|
669 |
public int indexOf(Object o) { |
670 |
final SequenceLock lock = this.lock; |
671 |
for (;;) { |
672 |
long seq = lock.awaitAvailability(); |
673 |
Object[] items = array; |
674 |
int n = count; |
675 |
if (n <= items.length) { |
676 |
for (int i = 0; i < n; ++i) { |
677 |
Object e = items[i]; |
678 |
if (lock.getSequence() != seq) { |
679 |
lock.lock(); |
680 |
try { |
681 |
return rawIndexOf(o, 0, count); |
682 |
} finally { |
683 |
lock.unlock(); |
684 |
} |
685 |
} |
686 |
else if ((o == null) ? e == null : o.equals(e)) |
687 |
return i; |
688 |
} |
689 |
return -1; |
690 |
} |
691 |
} |
692 |
} |
693 |
|
694 |
public boolean isEmpty() { |
695 |
return count == 0; |
696 |
} |
697 |
|
698 |
public Iterator<E> iterator() { |
699 |
return new Itr<E>(this, 0); |
700 |
} |
701 |
|
702 |
public int lastIndexOf(Object o) { |
703 |
final SequenceLock lock = this.lock; |
704 |
for (;;) { |
705 |
long seq = lock.awaitAvailability(); |
706 |
Object[] items = array; |
707 |
int n = count; |
708 |
if (n <= items.length) { |
709 |
for (int i = n - 1; i >= 0; --i) { |
710 |
Object e = items[i]; |
711 |
if (lock.getSequence() != seq) { |
712 |
lock.lock(); |
713 |
try { |
714 |
return rawLastIndexOf(o, 0, count); |
715 |
} finally { |
716 |
lock.unlock(); |
717 |
} |
718 |
} |
719 |
else if ((o == null) ? e == null : o.equals(e)) |
720 |
return i; |
721 |
} |
722 |
return -1; |
723 |
} |
724 |
} |
725 |
} |
726 |
|
727 |
public ListIterator<E> listIterator() { |
728 |
return new Itr<E>(this, 0); |
729 |
} |
730 |
|
731 |
public ListIterator<E> listIterator(int index) { |
732 |
return new Itr<E>(this, index); |
733 |
} |
734 |
|
735 |
public E remove(int index) { |
736 |
final SequenceLock lock = this.lock; |
737 |
lock.lock(); |
738 |
try { |
739 |
if (index < 0 || index >= count) |
740 |
throw new ArrayIndexOutOfBoundsException(index); |
741 |
@SuppressWarnings("unchecked") |
742 |
E oldValue = (E) array[index]; |
743 |
rawRemoveAt(index); |
744 |
return oldValue; |
745 |
} finally { |
746 |
lock.unlock(); |
747 |
} |
748 |
} |
749 |
|
750 |
public boolean remove(Object o) { |
751 |
final SequenceLock lock = this.lock; |
752 |
lock.lock(); |
753 |
try { |
754 |
return rawRemoveAt(rawIndexOf(o, 0, count)); |
755 |
} finally { |
756 |
lock.unlock(); |
757 |
} |
758 |
} |
759 |
|
760 |
public boolean removeAll(Collection<?> c) { |
761 |
return internalRemoveAll(c, 0, -1); |
762 |
} |
763 |
|
764 |
public boolean retainAll(Collection<?> c) { |
765 |
return internalRetainAll(c, 0, -1); |
766 |
} |
767 |
|
768 |
public E set(int index, E element) { |
769 |
final SequenceLock lock = this.lock; |
770 |
lock.lock(); |
771 |
try { |
772 |
Object[] items = array; |
773 |
if (index < 0 || index >= count) |
774 |
throw new ArrayIndexOutOfBoundsException(index); |
775 |
@SuppressWarnings("unchecked") |
776 |
E oldValue = (E) items[index]; |
777 |
items[index] = element; |
778 |
return oldValue; |
779 |
} finally { |
780 |
lock.unlock(); |
781 |
} |
782 |
} |
783 |
|
784 |
public int size() { |
785 |
return count; |
786 |
} |
787 |
|
788 |
public List<E> subList(int fromIndex, int toIndex) { |
789 |
int c = size(); |
790 |
int ssize = toIndex - fromIndex; |
791 |
if (fromIndex < 0 || toIndex > c || ssize < 0) |
792 |
throw new IndexOutOfBoundsException(); |
793 |
return new ReadMostlyVectorSublist<E>(this, fromIndex, ssize); |
794 |
} |
795 |
|
796 |
public Object[] toArray() { |
797 |
return internalToArray(0, -1); |
798 |
} |
799 |
|
800 |
public <T> T[] toArray(T[] a) { |
801 |
return internalToArray(a, 0, -1); |
802 |
} |
803 |
|
804 |
public String toString() { |
805 |
return internalToString(0, -1); |
806 |
} |
807 |
|
808 |
// ReadMostlyVector-only methods |
809 |
|
810 |
/** |
811 |
* Append the element if not present. |
812 |
* |
813 |
* @param e element to be added to this list, if absent |
814 |
* @return {@code true} if the element was added |
815 |
*/ |
816 |
public boolean addIfAbsent(E e) { |
817 |
final SequenceLock lock = this.lock; |
818 |
lock.lock(); |
819 |
try { |
820 |
if (rawIndexOf(e, 0, count) < 0) { |
821 |
rawAdd(e); |
822 |
return true; |
823 |
} |
824 |
else |
825 |
return false; |
826 |
} finally { |
827 |
lock.unlock(); |
828 |
} |
829 |
} |
830 |
|
831 |
/** |
832 |
* Appends all of the elements in the specified collection that |
833 |
* are not already contained in this list, to the end of |
834 |
* this list, in the order that they are returned by the |
835 |
* specified collection's iterator. |
836 |
* |
837 |
* @param c collection containing elements to be added to this list |
838 |
* @return the number of elements added |
839 |
* @throws NullPointerException if the specified collection is null |
840 |
* @see #addIfAbsent(Object) |
841 |
*/ |
842 |
public int addAllAbsent(Collection<? extends E> c) { |
843 |
int added = 0; |
844 |
Object[] cs = c.toArray(); |
845 |
int clen = cs.length; |
846 |
if (clen != 0) { |
847 |
lock.lock(); |
848 |
try { |
849 |
for (int i = 0; i < clen; ++i) { |
850 |
@SuppressWarnings("unchecked") |
851 |
E e = (E) cs[i]; |
852 |
if (rawIndexOf(e, 0, count) < 0) { |
853 |
rawAdd(e); |
854 |
++added; |
855 |
} |
856 |
} |
857 |
} finally { |
858 |
lock.unlock(); |
859 |
} |
860 |
} |
861 |
return added; |
862 |
} |
863 |
|
864 |
/** |
865 |
* Returns an iterator operating over a snapshot copy of the |
866 |
* elements of this collection created upon construction of the |
867 |
* iterator. The iterator does <em>NOT</em> support the |
868 |
* {@code remove} method. |
869 |
* |
870 |
* @return an iterator over the elements in this list in proper sequence |
871 |
*/ |
872 |
public Iterator<E> snapshotIterator() { |
873 |
return new SnapshotIterator<E>(this); |
874 |
} |
875 |
|
876 |
static final class SnapshotIterator<E> implements Iterator<E> { |
877 |
private final Object[] items; |
878 |
private int cursor; |
879 |
SnapshotIterator(ReadMostlyVector<E> v) { items = v.toArray(); } |
880 |
public boolean hasNext() { return cursor < items.length; } |
881 |
@SuppressWarnings("unchecked") |
882 |
public E next() { |
883 |
if (cursor < items.length) |
884 |
return (E) items[cursor++]; |
885 |
throw new NoSuchElementException(); |
886 |
} |
887 |
public void remove() { throw new UnsupportedOperationException() ; } |
888 |
} |
889 |
|
890 |
// Vector-only methods |
891 |
|
892 |
/** See {@link Vector#firstElement} */ |
893 |
public E firstElement() { |
894 |
final SequenceLock lock = this.lock; |
895 |
for (;;) { |
896 |
long seq = lock.awaitAvailability(); |
897 |
Object[] items = array; |
898 |
int len = items.length; |
899 |
int n = count; |
900 |
if (n > len) |
901 |
continue; |
902 |
boolean empty = (n == 0); |
903 |
@SuppressWarnings("unchecked") |
904 |
E e = empty ? null : (E) items[0]; |
905 |
if (lock.getSequence() == seq) { |
906 |
if (empty) |
907 |
throw new NoSuchElementException(); |
908 |
else |
909 |
return e; |
910 |
} |
911 |
} |
912 |
} |
913 |
|
914 |
/** See {@link Vector#lastElement} */ |
915 |
public E lastElement() { |
916 |
final SequenceLock lock = this.lock; |
917 |
for (;;) { |
918 |
long seq = lock.awaitAvailability(); |
919 |
Object[] items = array; |
920 |
int len = items.length; |
921 |
int n = count; |
922 |
if (n > len) |
923 |
continue; |
924 |
boolean empty = (n == 0); |
925 |
@SuppressWarnings("unchecked") |
926 |
E e = empty ? null : (E) items[n - 1]; |
927 |
if (lock.getSequence() == seq) { |
928 |
if (empty) |
929 |
throw new NoSuchElementException(); |
930 |
else |
931 |
return e; |
932 |
} |
933 |
} |
934 |
} |
935 |
|
936 |
/** See {@link Vector#indexOf(Object, int)} */ |
937 |
public int indexOf(Object o, int index) { |
938 |
final SequenceLock lock = this.lock; |
939 |
int idx = 0; |
940 |
boolean ex = false; |
941 |
long seq = lock.awaitAvailability(); |
942 |
Object[] items = array; |
943 |
int n = count; |
944 |
boolean retry = false; |
945 |
if (n > items.length) |
946 |
retry = true; |
947 |
else if (index < 0) |
948 |
ex = true; |
949 |
else |
950 |
idx = validatedIndexOf(o, items, index, n, seq); |
951 |
if (retry || lock.getSequence() != seq) { |
952 |
lock.lock(); |
953 |
try { |
954 |
if (index < 0) |
955 |
ex = true; |
956 |
else |
957 |
idx = rawIndexOf(o, index, count); |
958 |
} finally { |
959 |
lock.unlock(); |
960 |
} |
961 |
} |
962 |
if (ex) |
963 |
throw new ArrayIndexOutOfBoundsException(index); |
964 |
return idx; |
965 |
} |
966 |
|
967 |
/** See {@link Vector#lastIndexOf(Object, int)} */ |
968 |
public int lastIndexOf(Object o, int index) { |
969 |
final SequenceLock lock = this.lock; |
970 |
int idx = 0; |
971 |
boolean ex = false; |
972 |
long seq = lock.awaitAvailability(); |
973 |
Object[] items = array; |
974 |
int n = count; |
975 |
boolean retry = false; |
976 |
if (n > items.length) |
977 |
retry = true; |
978 |
else if (index >= n) |
979 |
ex = true; |
980 |
else |
981 |
idx = validatedLastIndexOf(o, items, index, 0, seq); |
982 |
if (retry || lock.getSequence() != seq) { |
983 |
lock.lock(); |
984 |
try { |
985 |
if (index >= count) |
986 |
ex = true; |
987 |
else |
988 |
idx = rawLastIndexOf(o, index, 0); |
989 |
} finally { |
990 |
lock.unlock(); |
991 |
} |
992 |
} |
993 |
if (ex) |
994 |
throw new ArrayIndexOutOfBoundsException(index); |
995 |
return idx; |
996 |
} |
997 |
|
998 |
/** See {@link Vector#setSize} */ |
999 |
public void setSize(int newSize) { |
1000 |
if (newSize < 0) |
1001 |
throw new ArrayIndexOutOfBoundsException(newSize); |
1002 |
final SequenceLock lock = this.lock; |
1003 |
lock.lock(); |
1004 |
try { |
1005 |
int n = count; |
1006 |
if (newSize > n) |
1007 |
grow(newSize); |
1008 |
else { |
1009 |
Object[] items = array; |
1010 |
for (int i = newSize ; i < n ; i++) |
1011 |
items[i] = null; |
1012 |
} |
1013 |
count = newSize; |
1014 |
} finally { |
1015 |
lock.unlock(); |
1016 |
} |
1017 |
} |
1018 |
|
1019 |
/** See {@link Vector#copyInto} */ |
1020 |
public void copyInto(Object[] anArray) { |
1021 |
final SequenceLock lock = this.lock; |
1022 |
lock.lock(); |
1023 |
try { |
1024 |
System.arraycopy(array, 0, anArray, 0, count); |
1025 |
} finally { |
1026 |
lock.unlock(); |
1027 |
} |
1028 |
} |
1029 |
|
1030 |
/** See {@link Vector#trimToSize} */ |
1031 |
public void trimToSize() { |
1032 |
final SequenceLock lock = this.lock; |
1033 |
lock.lock(); |
1034 |
try { |
1035 |
Object[] items = array; |
1036 |
int n = count; |
1037 |
if (n < items.length) |
1038 |
array = Arrays.copyOf(items, n); |
1039 |
} finally { |
1040 |
lock.unlock(); |
1041 |
} |
1042 |
} |
1043 |
|
1044 |
/** See {@link Vector#ensureCapacity} */ |
1045 |
public void ensureCapacity(int minCapacity) { |
1046 |
if (minCapacity > 0) { |
1047 |
final SequenceLock lock = this.lock; |
1048 |
lock.lock(); |
1049 |
try { |
1050 |
if (minCapacity - array.length > 0) |
1051 |
grow(minCapacity); |
1052 |
} finally { |
1053 |
lock.unlock(); |
1054 |
} |
1055 |
} |
1056 |
} |
1057 |
|
1058 |
/** See {@link Vector#elements} */ |
1059 |
public Enumeration<E> elements() { |
1060 |
return new Itr<E>(this, 0); |
1061 |
} |
1062 |
|
1063 |
/** See {@link Vector#capacity} */ |
1064 |
public int capacity() { |
1065 |
return array.length; |
1066 |
} |
1067 |
|
1068 |
/** See {@link Vector#elementAt} */ |
1069 |
public E elementAt(int index) { |
1070 |
return get(index); |
1071 |
} |
1072 |
|
1073 |
/** See {@link Vector#setElementAt} */ |
1074 |
public void setElementAt(E obj, int index) { |
1075 |
set(index, obj); |
1076 |
} |
1077 |
|
1078 |
/** See {@link Vector#removeElementAt} */ |
1079 |
public void removeElementAt(int index) { |
1080 |
remove(index); |
1081 |
} |
1082 |
|
1083 |
/** See {@link Vector#insertElementAt} */ |
1084 |
public void insertElementAt(E obj, int index) { |
1085 |
add(index, obj); |
1086 |
} |
1087 |
|
1088 |
/** See {@link Vector#addElement} */ |
1089 |
public void addElement(E obj) { |
1090 |
add(obj); |
1091 |
} |
1092 |
|
1093 |
/** See {@link Vector#removeElement} */ |
1094 |
public boolean removeElement(Object obj) { |
1095 |
return remove(obj); |
1096 |
} |
1097 |
|
1098 |
/** See {@link Vector#removeAllElements} */ |
1099 |
public void removeAllElements() { |
1100 |
clear(); |
1101 |
} |
1102 |
|
1103 |
// other methods |
1104 |
|
1105 |
public ReadMostlyVector<E> clone() { |
1106 |
final SequenceLock lock = this.lock; |
1107 |
Object[] a = null; |
1108 |
boolean retry = false; |
1109 |
long seq = lock.awaitAvailability(); |
1110 |
Object[] items = array; |
1111 |
int n = count; |
1112 |
if (n <= items.length) |
1113 |
a = Arrays.copyOf(items, n); |
1114 |
else |
1115 |
retry = true; |
1116 |
if (retry || lock.getSequence() != seq) { |
1117 |
lock.lock(); |
1118 |
try { |
1119 |
n = count; |
1120 |
a = Arrays.copyOf(array, n); |
1121 |
} finally { |
1122 |
lock.unlock(); |
1123 |
} |
1124 |
} |
1125 |
return new ReadMostlyVector<E>(a, n, capacityIncrement); |
1126 |
} |
1127 |
|
1128 |
private void writeObject(java.io.ObjectOutputStream s) |
1129 |
throws java.io.IOException { |
1130 |
final SequenceLock lock = this.lock; |
1131 |
lock.lock(); |
1132 |
try { |
1133 |
s.defaultWriteObject(); |
1134 |
} finally { |
1135 |
lock.unlock(); |
1136 |
} |
1137 |
} |
1138 |
|
1139 |
static final class Itr<E> implements ListIterator<E>, Enumeration<E> { |
1140 |
final ReadMostlyVector<E> list; |
1141 |
final SequenceLock lock; |
1142 |
Object[] items; |
1143 |
E next, prev; |
1144 |
long seq; |
1145 |
int cursor; |
1146 |
int fence; |
1147 |
int lastRet; |
1148 |
boolean validNext, validPrev; |
1149 |
|
1150 |
Itr(ReadMostlyVector<E> list, int index) { |
1151 |
this.list = list; |
1152 |
this.lock = list.lock; |
1153 |
this.cursor = index; |
1154 |
this.lastRet = -1; |
1155 |
refresh(); |
1156 |
if (index < 0 || index > fence) |
1157 |
throw new ArrayIndexOutOfBoundsException(index); |
1158 |
} |
1159 |
|
1160 |
private void refresh() { |
1161 |
validNext = validPrev = false; |
1162 |
do { |
1163 |
seq = lock.awaitAvailability(); |
1164 |
items = list.array; |
1165 |
} while ((fence = list.count) > items.length || |
1166 |
lock.getSequence() != seq); |
1167 |
} |
1168 |
|
1169 |
@SuppressWarnings("unchecked") |
1170 |
public boolean hasNext() { |
1171 |
boolean valid; |
1172 |
int i = cursor; |
1173 |
for (;;) { |
1174 |
if (i >= fence || i < 0 || i >= items.length) { |
1175 |
valid = false; |
1176 |
break; |
1177 |
} |
1178 |
next = (E) items[i]; |
1179 |
if (lock.getSequence() == seq) { |
1180 |
valid = true; |
1181 |
break; |
1182 |
} |
1183 |
refresh(); |
1184 |
} |
1185 |
return validNext = valid; |
1186 |
} |
1187 |
|
1188 |
@SuppressWarnings("unchecked") |
1189 |
public boolean hasPrevious() { |
1190 |
boolean valid; |
1191 |
int i = cursor - 1; |
1192 |
for (;;) { |
1193 |
if (i >= fence || i < 0 || i >= items.length) { |
1194 |
valid = false; |
1195 |
break; |
1196 |
} |
1197 |
prev = (E) items[i]; |
1198 |
if (lock.getSequence() == seq) { |
1199 |
valid = true; |
1200 |
break; |
1201 |
} |
1202 |
refresh(); |
1203 |
} |
1204 |
return validPrev = valid; |
1205 |
} |
1206 |
|
1207 |
public E next() { |
1208 |
if (validNext || hasNext()) { |
1209 |
validNext = false; |
1210 |
lastRet = cursor++; |
1211 |
return next; |
1212 |
} |
1213 |
throw new NoSuchElementException(); |
1214 |
} |
1215 |
|
1216 |
public E previous() { |
1217 |
if (validPrev || hasPrevious()) { |
1218 |
validPrev = false; |
1219 |
lastRet = cursor--; |
1220 |
return prev; |
1221 |
} |
1222 |
throw new NoSuchElementException(); |
1223 |
} |
1224 |
|
1225 |
public void remove() { |
1226 |
int i = lastRet; |
1227 |
if (i < 0) |
1228 |
throw new IllegalStateException(); |
1229 |
lock.lock(); |
1230 |
try { |
1231 |
if (i < list.count) |
1232 |
list.remove(i); |
1233 |
} finally { |
1234 |
lock.unlock(); |
1235 |
} |
1236 |
cursor = i; |
1237 |
lastRet = -1; |
1238 |
refresh(); |
1239 |
} |
1240 |
|
1241 |
public void set(E e) { |
1242 |
int i = lastRet; |
1243 |
if (i < 0) |
1244 |
throw new IllegalStateException(); |
1245 |
lock.lock(); |
1246 |
try { |
1247 |
if (i < list.count) |
1248 |
list.set(i, e); |
1249 |
} finally { |
1250 |
lock.unlock(); |
1251 |
} |
1252 |
refresh(); |
1253 |
} |
1254 |
|
1255 |
public void add(E e) { |
1256 |
int i = cursor; |
1257 |
if (i < 0) |
1258 |
throw new IllegalStateException(); |
1259 |
lock.lock(); |
1260 |
try { |
1261 |
if (i <= list.count) |
1262 |
list.add(i, e); |
1263 |
} finally { |
1264 |
lock.unlock(); |
1265 |
} |
1266 |
cursor = i + 1; |
1267 |
lastRet = -1; |
1268 |
refresh(); |
1269 |
} |
1270 |
|
1271 |
public boolean hasMoreElements() { return hasNext(); } |
1272 |
public E nextElement() { return next(); } |
1273 |
public int nextIndex() { return cursor; } |
1274 |
public int previousIndex() { return cursor - 1; } |
1275 |
} |
1276 |
|
1277 |
static final class ReadMostlyVectorSublist<E> |
1278 |
implements List<E>, RandomAccess, java.io.Serializable { |
1279 |
static final long serialVersionUID = 3041673470172026059L; |
1280 |
|
1281 |
final ReadMostlyVector<E> list; |
1282 |
final int offset; |
1283 |
volatile int size; |
1284 |
|
1285 |
ReadMostlyVectorSublist(ReadMostlyVector<E> list, |
1286 |
int offset, int size) { |
1287 |
this.list = list; |
1288 |
this.offset = offset; |
1289 |
this.size = size; |
1290 |
} |
1291 |
|
1292 |
private void rangeCheck(int index) { |
1293 |
if (index < 0 || index >= size) |
1294 |
throw new ArrayIndexOutOfBoundsException(index); |
1295 |
} |
1296 |
|
1297 |
public boolean add(E element) { |
1298 |
final SequenceLock lock = list.lock; |
1299 |
lock.lock(); |
1300 |
try { |
1301 |
int c = size; |
1302 |
list.rawAddAt(c + offset, element); |
1303 |
size = c + 1; |
1304 |
} finally { |
1305 |
lock.unlock(); |
1306 |
} |
1307 |
return true; |
1308 |
} |
1309 |
|
1310 |
public void add(int index, E element) { |
1311 |
final SequenceLock lock = list.lock; |
1312 |
lock.lock(); |
1313 |
try { |
1314 |
if (index < 0 || index > size) |
1315 |
throw new ArrayIndexOutOfBoundsException(index); |
1316 |
list.rawAddAt(index + offset, element); |
1317 |
++size; |
1318 |
} finally { |
1319 |
lock.unlock(); |
1320 |
} |
1321 |
} |
1322 |
|
1323 |
public boolean addAll(Collection<? extends E> c) { |
1324 |
Object[] elements = c.toArray(); |
1325 |
final SequenceLock lock = list.lock; |
1326 |
lock.lock(); |
1327 |
try { |
1328 |
int s = size; |
1329 |
int pc = list.count; |
1330 |
list.rawAddAllAt(offset + s, elements); |
1331 |
int added = list.count - pc; |
1332 |
size = s + added; |
1333 |
return added != 0; |
1334 |
} finally { |
1335 |
lock.unlock(); |
1336 |
} |
1337 |
} |
1338 |
|
1339 |
public boolean addAll(int index, Collection<? extends E> c) { |
1340 |
Object[] elements = c.toArray(); |
1341 |
final SequenceLock lock = list.lock; |
1342 |
lock.lock(); |
1343 |
try { |
1344 |
int s = size; |
1345 |
if (index < 0 || index > s) |
1346 |
throw new ArrayIndexOutOfBoundsException(index); |
1347 |
int pc = list.count; |
1348 |
list.rawAddAllAt(index + offset, elements); |
1349 |
int added = list.count - pc; |
1350 |
size = s + added; |
1351 |
return added != 0; |
1352 |
} finally { |
1353 |
lock.unlock(); |
1354 |
} |
1355 |
} |
1356 |
|
1357 |
public void clear() { |
1358 |
final SequenceLock lock = list.lock; |
1359 |
lock.lock(); |
1360 |
try { |
1361 |
list.internalClear(offset, offset + size); |
1362 |
size = 0; |
1363 |
} finally { |
1364 |
lock.unlock(); |
1365 |
} |
1366 |
} |
1367 |
|
1368 |
public boolean contains(Object o) { |
1369 |
return indexOf(o) >= 0; |
1370 |
} |
1371 |
|
1372 |
public boolean containsAll(Collection<?> c) { |
1373 |
return list.internalContainsAll(c, offset, offset + size); |
1374 |
} |
1375 |
|
1376 |
public boolean equals(Object o) { |
1377 |
if (o == this) |
1378 |
return true; |
1379 |
if (!(o instanceof List)) |
1380 |
return false; |
1381 |
return list.internalEquals((List<?>)(o), offset, offset + size); |
1382 |
} |
1383 |
|
1384 |
public E get(int index) { |
1385 |
if (index < 0 || index >= size) |
1386 |
throw new ArrayIndexOutOfBoundsException(index); |
1387 |
return list.get(index + offset); |
1388 |
} |
1389 |
|
1390 |
public int hashCode() { |
1391 |
return list.internalHashCode(offset, offset + size); |
1392 |
} |
1393 |
|
1394 |
public int indexOf(Object o) { |
1395 |
final SequenceLock lock = list.lock; |
1396 |
long seq = lock.awaitAvailability(); |
1397 |
Object[] items = list.array; |
1398 |
int c = list.count; |
1399 |
if (c <= items.length) { |
1400 |
int idx = list.validatedIndexOf(o, items, offset, |
1401 |
offset + size, seq); |
1402 |
if (lock.getSequence() == seq) |
1403 |
return idx < 0 ? -1 : idx - offset; |
1404 |
} |
1405 |
lock.lock(); |
1406 |
try { |
1407 |
int idx = list.rawIndexOf(o, offset, offset + size); |
1408 |
return idx < 0 ? -1 : idx - offset; |
1409 |
} finally { |
1410 |
lock.unlock(); |
1411 |
} |
1412 |
} |
1413 |
|
1414 |
public boolean isEmpty() { |
1415 |
return size == 0; |
1416 |
} |
1417 |
|
1418 |
public Iterator<E> iterator() { |
1419 |
return new SubItr<E>(this, offset); |
1420 |
} |
1421 |
|
1422 |
public int lastIndexOf(Object o) { |
1423 |
final SequenceLock lock = list.lock; |
1424 |
long seq = lock.awaitAvailability(); |
1425 |
Object[] items = list.array; |
1426 |
int c = list.count; |
1427 |
if (c <= items.length) { |
1428 |
int idx = list.validatedLastIndexOf(o, items, offset+size-1, |
1429 |
offset, seq); |
1430 |
if (lock.getSequence() == seq) |
1431 |
return idx < 0 ? -1 : idx - offset; |
1432 |
} |
1433 |
lock.lock(); |
1434 |
try { |
1435 |
int idx = list.rawLastIndexOf(o, offset + size - 1, offset); |
1436 |
return idx < 0 ? -1 : idx - offset; |
1437 |
} finally { |
1438 |
lock.unlock(); |
1439 |
} |
1440 |
} |
1441 |
|
1442 |
public ListIterator<E> listIterator() { |
1443 |
return new SubItr<E>(this, offset); |
1444 |
} |
1445 |
|
1446 |
public ListIterator<E> listIterator(int index) { |
1447 |
return new SubItr<E>(this, index + offset); |
1448 |
} |
1449 |
|
1450 |
public E remove(int index) { |
1451 |
final SequenceLock lock = list.lock; |
1452 |
lock.lock(); |
1453 |
try { |
1454 |
Object[] items = list.array; |
1455 |
int i = index + offset; |
1456 |
if (index < 0 || index >= size || i >= items.length) |
1457 |
throw new ArrayIndexOutOfBoundsException(index); |
1458 |
@SuppressWarnings("unchecked") |
1459 |
E result = (E) items[i]; |
1460 |
list.rawRemoveAt(i); |
1461 |
size--; |
1462 |
return result; |
1463 |
} finally { |
1464 |
lock.unlock(); |
1465 |
} |
1466 |
} |
1467 |
|
1468 |
public boolean remove(Object o) { |
1469 |
final SequenceLock lock = list.lock; |
1470 |
lock.lock(); |
1471 |
try { |
1472 |
if (list.rawRemoveAt(list.rawIndexOf(o, offset, |
1473 |
offset + size))) { |
1474 |
--size; |
1475 |
return true; |
1476 |
} |
1477 |
else |
1478 |
return false; |
1479 |
} finally { |
1480 |
lock.unlock(); |
1481 |
} |
1482 |
} |
1483 |
|
1484 |
public boolean removeAll(Collection<?> c) { |
1485 |
return list.internalRemoveAll(c, offset, offset + size); |
1486 |
} |
1487 |
|
1488 |
public boolean retainAll(Collection<?> c) { |
1489 |
return list.internalRetainAll(c, offset, offset + size); |
1490 |
} |
1491 |
|
1492 |
public E set(int index, E element) { |
1493 |
if (index < 0 || index >= size) |
1494 |
throw new ArrayIndexOutOfBoundsException(index); |
1495 |
return list.set(index+offset, element); |
1496 |
} |
1497 |
|
1498 |
public int size() { |
1499 |
return size; |
1500 |
} |
1501 |
|
1502 |
public List<E> subList(int fromIndex, int toIndex) { |
1503 |
int c = size; |
1504 |
int ssize = toIndex - fromIndex; |
1505 |
if (fromIndex < 0 || toIndex > c || ssize < 0) |
1506 |
throw new IndexOutOfBoundsException(); |
1507 |
return new ReadMostlyVectorSublist<E>(list, offset+fromIndex, ssize); |
1508 |
} |
1509 |
|
1510 |
public Object[] toArray() { |
1511 |
return list.internalToArray(offset, offset + size); |
1512 |
} |
1513 |
|
1514 |
public <T> T[] toArray(T[] a) { |
1515 |
return list.internalToArray(a, offset, offset + size); |
1516 |
} |
1517 |
|
1518 |
public String toString() { |
1519 |
return list.internalToString(offset, offset + size); |
1520 |
} |
1521 |
|
1522 |
} |
1523 |
|
1524 |
static final class SubItr<E> implements ListIterator<E> { |
1525 |
final ReadMostlyVectorSublist<E> sublist; |
1526 |
final ReadMostlyVector<E> list; |
1527 |
final SequenceLock lock; |
1528 |
Object[] items; |
1529 |
E next, prev; |
1530 |
long seq; |
1531 |
int cursor; |
1532 |
int fence; |
1533 |
int lastRet; |
1534 |
boolean validNext, validPrev; |
1535 |
|
1536 |
SubItr(ReadMostlyVectorSublist<E> sublist, int index) { |
1537 |
this.sublist = sublist; |
1538 |
this.list = sublist.list; |
1539 |
this.lock = list.lock; |
1540 |
this.cursor = index; |
1541 |
this.lastRet = -1; |
1542 |
refresh(); |
1543 |
if (index < 0 || index > fence) |
1544 |
throw new ArrayIndexOutOfBoundsException(index); |
1545 |
} |
1546 |
|
1547 |
private void refresh() { |
1548 |
validNext = validPrev = false; |
1549 |
do { |
1550 |
int n; |
1551 |
seq = lock.awaitAvailability(); |
1552 |
items = list.array; |
1553 |
if ((n = list.count) > items.length) |
1554 |
continue; |
1555 |
int b = sublist.offset + sublist.size; |
1556 |
fence = b < n ? b : n; |
1557 |
} while (lock.getSequence() != seq); |
1558 |
} |
1559 |
|
1560 |
@SuppressWarnings("unchecked") |
1561 |
public boolean hasNext() { |
1562 |
boolean valid; |
1563 |
int i = cursor; |
1564 |
for (;;) { |
1565 |
if (i >= fence || i < 0 || i >= items.length) { |
1566 |
valid = false; |
1567 |
break; |
1568 |
} |
1569 |
next = (E) items[i]; |
1570 |
if (lock.getSequence() == seq) { |
1571 |
valid = true; |
1572 |
break; |
1573 |
} |
1574 |
refresh(); |
1575 |
} |
1576 |
return validNext = valid; |
1577 |
} |
1578 |
|
1579 |
@SuppressWarnings("unchecked") |
1580 |
public boolean hasPrevious() { |
1581 |
boolean valid; |
1582 |
int i = cursor - 1; |
1583 |
for (;;) { |
1584 |
if (i >= fence || i < 0 || i >= items.length) { |
1585 |
valid = false; |
1586 |
break; |
1587 |
} |
1588 |
prev = (E) items[i]; |
1589 |
if (lock.getSequence() == seq) { |
1590 |
valid = true; |
1591 |
break; |
1592 |
} |
1593 |
refresh(); |
1594 |
} |
1595 |
return validPrev = valid; |
1596 |
} |
1597 |
|
1598 |
public E next() { |
1599 |
if (validNext || hasNext()) { |
1600 |
validNext = false; |
1601 |
lastRet = cursor++; |
1602 |
return next; |
1603 |
} |
1604 |
throw new NoSuchElementException(); |
1605 |
} |
1606 |
|
1607 |
public E previous() { |
1608 |
if (validPrev || hasPrevious()) { |
1609 |
validPrev = false; |
1610 |
lastRet = cursor--; |
1611 |
return prev; |
1612 |
} |
1613 |
throw new NoSuchElementException(); |
1614 |
} |
1615 |
|
1616 |
public int nextIndex() { |
1617 |
return cursor - sublist.offset; |
1618 |
} |
1619 |
|
1620 |
public int previousIndex() { |
1621 |
return cursor - 1 - sublist.offset; |
1622 |
} |
1623 |
|
1624 |
public void remove() { |
1625 |
int i = lastRet; |
1626 |
if (i < 0) |
1627 |
throw new IllegalStateException(); |
1628 |
cursor = i; |
1629 |
lastRet = -1; |
1630 |
lock.lock(); |
1631 |
try { |
1632 |
if (i < list.count) { |
1633 |
list.remove(i); |
1634 |
--sublist.size; |
1635 |
} |
1636 |
} finally { |
1637 |
lock.unlock(); |
1638 |
} |
1639 |
refresh(); |
1640 |
} |
1641 |
|
1642 |
public void set(E e) { |
1643 |
int i = lastRet; |
1644 |
if (i < 0) |
1645 |
throw new IllegalStateException(); |
1646 |
lock.lock(); |
1647 |
try { |
1648 |
if (i < list.count) |
1649 |
list.set(i, e); |
1650 |
} finally { |
1651 |
lock.unlock(); |
1652 |
} |
1653 |
refresh(); |
1654 |
} |
1655 |
|
1656 |
public void add(E e) { |
1657 |
int i = cursor; |
1658 |
if (i < 0) |
1659 |
throw new IllegalStateException(); |
1660 |
cursor = i + 1; |
1661 |
lastRet = -1; |
1662 |
lock.lock(); |
1663 |
try { |
1664 |
if (i <= list.count) { |
1665 |
list.add(i, e); |
1666 |
++sublist.size; |
1667 |
} |
1668 |
} finally { |
1669 |
lock.unlock(); |
1670 |
} |
1671 |
refresh(); |
1672 |
} |
1673 |
|
1674 |
} |
1675 |
} |
1676 |
|