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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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import java.util.*; |
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import java.util.concurrent.*; |
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import java.util.concurrent.locks.*; |
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|
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/** |
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* This is an incomplete implementation of a wrapper class |
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* that places read-write locks around unsynchronized Collections. |
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* Exists as a sample input for CollectionLoops test. |
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*/ |
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public final class RWCollection<E> implements Collection<E> { |
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private final Collection c; |
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private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock(); |
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|
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public RWCollection(Collection<E> c) { |
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if (c == null) |
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throw new NullPointerException(); |
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this.c = c; |
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} |
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|
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public RWCollection() { |
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this(new ArrayList<E>()); |
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} |
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|
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public final int size() { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.size(); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean isEmpty() { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.isEmpty(); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean contains(Object o) { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.contains(o); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean equals(Object o) { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.equals(o); } |
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finally { l.unlock(); } |
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} |
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|
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public final int hashCode() { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.hashCode(); } |
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finally { l.unlock(); } |
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} |
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|
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public final String toString() { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.toString(); } |
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finally { l.unlock(); } |
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} |
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|
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public final Iterator<E> iterator() { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.iterator(); } |
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finally { l.unlock(); } |
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} |
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|
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public final Object[] toArray() { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return c.toArray(); } |
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finally { l.unlock(); } |
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} |
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|
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public final <T> T[] toArray(T[] a) { |
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final ReentrantReadWriteLock.ReadLock l = rwl.readLock(); |
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l.lock(); |
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try { return (T[])c.toArray(a); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean add(E e) { |
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final ReentrantReadWriteLock.WriteLock l = rwl.writeLock(); |
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l.lock(); |
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try { return c.add(e); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean remove(Object o) { |
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final ReentrantReadWriteLock.WriteLock l = rwl.writeLock(); |
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l.lock(); |
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try { return c.remove(o); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean containsAll(Collection<?> coll) { |
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final ReentrantReadWriteLock.WriteLock l = rwl.writeLock(); |
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l.lock(); |
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try { return c.containsAll(coll); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean addAll(Collection<? extends E> coll) { |
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final ReentrantReadWriteLock.WriteLock l = rwl.writeLock(); |
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l.lock(); |
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try { return c.addAll(coll); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean removeAll(Collection<?> coll) { |
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final ReentrantReadWriteLock.WriteLock l = rwl.writeLock(); |
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l.lock(); |
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try { return c.removeAll(coll); } |
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finally { l.unlock(); } |
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} |
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|
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public final boolean retainAll(Collection<?> coll) { |
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final ReentrantReadWriteLock.WriteLock l = rwl.writeLock(); |
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l.lock(); |
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try { return c.retainAll(coll); } |
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finally { l.unlock(); } |
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} |
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|
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public final void clear() { |
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final ReentrantReadWriteLock.WriteLock l = rwl.writeLock(); |
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l.lock(); |
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try { c.clear(); } |
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finally { l.unlock(); } |
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} |
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|
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} |
