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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 java.util.concurrent.locks; |
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|
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/** |
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* A synchronizer that may be exclusively owned by a thread. This |
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* class provides a basis for creating locks and related synchronizers |
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* that may entail a notion of ownership. The |
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* {@code AbstractOwnableSynchronizer} class itself does not manage or |
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* use this information. However, subclasses and tools may use |
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* appropriately maintained values to help control and monitor access |
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* and provide diagnostics. |
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* |
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* @since 1.6 |
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* @author Doug Lea |
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*/ |
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public abstract class AbstractOwnableSynchronizer |
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implements java.io.Serializable { |
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|
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/** Use serial ID even though all fields transient. */ |
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private static final long serialVersionUID = 3737899427754241961L; |
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|
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/** |
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* Empty constructor for use by subclasses. |
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*/ |
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protected AbstractOwnableSynchronizer() { } |
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|
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/** |
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* The current owner of exclusive mode synchronization. |
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*/ |
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private transient Thread exclusiveOwnerThread; |
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|
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/** |
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* Sets the thread that currently owns exclusive access. |
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* A {@code null} argument indicates that no thread owns access. |
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* This method does not otherwise impose any synchronization or |
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* {@code volatile} field accesses. |
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* @param thread the owner thread |
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*/ |
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protected final void setExclusiveOwnerThread(Thread thread) { |
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exclusiveOwnerThread = thread; |
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} |
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|
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/** |
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* Returns the thread last set by {@code setExclusiveOwnerThread}, |
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* or {@code null} if never set. This method does not otherwise |
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* impose any synchronization or {@code volatile} field accesses. |
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* @return the owner thread |
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*/ |
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protected final Thread getExclusiveOwnerThread() { |
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return exclusiveOwnerThread; |
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} |
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} |
