@Beta
public abstract static class Monitor.Guard
extends Object

A boolean condition for which a thread may wait. A Guard is associated with a single Monitor. The monitor may check the guard at arbitrary times from any thread occupying the monitor, so code should not be written to rely on how often a guard might or might not be checked.

If a Guard is passed into any method of a Monitor other than the one it is associated with, an IllegalMonitorStateException is thrown.