Empty constructor for use by subclasses.
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
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. @param thread the owner thread
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.
@author Doug Lea