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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. Use, modify, and |
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* redistribute this code in any way without acknowledgement. |
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*/ |
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|
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package java.util.concurrent; |
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import java.util.concurrent.atomic.*; |
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|
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/** |
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* A linked list node supporting atomic operations on both item and |
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* next fields, Used by non-blocking linked-list based classes. |
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* @since 1.5 |
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* @author Doug Lea |
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*/ |
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|
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final class AtomicLinkedNode { |
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private volatile Object item; |
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private volatile AtomicLinkedNode next; |
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|
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private static final AtomicReferenceFieldUpdater<AtomicLinkedNode, AtomicLinkedNode> nextUpdater = |
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new AtomicReferenceFieldUpdater<AtomicLinkedNode, AtomicLinkedNode>(AtomicLinkedNode.class, AtomicLinkedNode.class, "next"); |
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private static final AtomicReferenceFieldUpdater<AtomicLinkedNode, Object> itemUpdater |
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= new AtomicReferenceFieldUpdater<AtomicLinkedNode, Object>(AtomicLinkedNode.class, Object.class, "item"); |
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|
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AtomicLinkedNode(Object x) { item = x; } |
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|
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AtomicLinkedNode(Object x, AtomicLinkedNode n) { item = x; next = n; } |
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|
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Object getItem() { |
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return item; |
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} |
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|
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boolean casItem(Object cmp, Object val) { |
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return itemUpdater.compareAndSet(this, cmp, val); |
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} |
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|
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void setItem(Object val) { |
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itemUpdater.set(this, val); |
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} |
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|
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AtomicLinkedNode getNext() { |
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return next; |
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} |
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|
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boolean casNext(AtomicLinkedNode cmp, AtomicLinkedNode val) { |
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return nextUpdater.compareAndSet(this, cmp, val); |
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} |
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|
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void setNext(AtomicLinkedNode val) { |
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nextUpdater.set(this, val); |
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} |
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|
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} |
