java.util.concurrent.locks.AbstractOwnableSynchronizer Maven / Gradle / Ivy
/*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
*/
package java.util.concurrent.locks;
/**
* A synchronizer that may be exclusively owned by a thread. This
* class provides a basis for creating locks and related synchronizers
* that may entail a notion of ownership. The
* {@code AbstractOwnableSynchronizer} class itself does not manage or
* use this information. However, subclasses and tools may use
* appropriately maintained values to help control and monitor access
* and provide diagnostics.
*
* @since 1.6
* @author Doug Lea
*/
public abstract class AbstractOwnableSynchronizer
implements java.io.Serializable {
/** Use serial ID even though all fields transient. */
private static final long serialVersionUID = 3737899427754241961L;
/**
* Empty constructor for use by subclasses.
*/
protected AbstractOwnableSynchronizer() { }
/**
* The current owner of exclusive mode synchronization.
*/
private transient Thread exclusiveOwnerThread;
/**
* Sets the thread that currently owns exclusive access. A
* {@code null} argument indicates that no thread owns access.
* This method does not otherwise impose any synchronization or
* {@code volatile} field accesses.
*/
protected final void setExclusiveOwnerThread(Thread t) {
exclusiveOwnerThread = t;
}
/**
* Returns the thread last set by
* {@code setExclusiveOwnerThread}, or {@code null} if never
* set. This method does not otherwise impose any synchronization
* or {@code volatile} field accesses.
* @return the owner thread
*/
protected final Thread getExclusiveOwnerThread() {
return exclusiveOwnerThread;
}
}