rt/emul/compact/src/main/java/java/util/concurrent/locks/AbstractOwnableSynchronizer.java
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36 package java.util.concurrent.locks;
39 * A synchronizer that may be exclusively owned by a thread. This
40 * class provides a basis for creating locks and related synchronizers
41 * that may entail a notion of ownership. The
42 * <tt>AbstractOwnableSynchronizer</tt> class itself does not manage or
43 * use this information. However, subclasses and tools may use
44 * appropriately maintained values to help control and monitor access
45 * and provide diagnostics.
50 public abstract class AbstractOwnableSynchronizer
51 implements java.io.Serializable {
53 /** Use serial ID even though all fields transient. */
54 private static final long serialVersionUID = 3737899427754241961L;
57 * Empty constructor for use by subclasses.
59 protected AbstractOwnableSynchronizer() { }
62 * The current owner of exclusive mode synchronization.
64 private transient Thread exclusiveOwnerThread;
67 * Sets the thread that currently owns exclusive access. A
68 * <tt>null</tt> argument indicates that no thread owns access.
69 * This method does not otherwise impose any synchronization or
70 * <tt>volatile</tt> field accesses.
72 protected final void setExclusiveOwnerThread(Thread t) {
73 exclusiveOwnerThread = t;
77 * Returns the thread last set by
78 * <tt>setExclusiveOwnerThread</tt>, or <tt>null</tt> if never
79 * set. This method does not otherwise impose any synchronization
80 * or <tt>volatile</tt> field accesses.
81 * @return the owner thread
83 protected final Thread getExclusiveOwnerThread() {
84 return exclusiveOwnerThread;