WaitSemaphore.java |
/* * JBoss, the OpenSource J2EE webOS * * Distributable under LGPL license. * See terms of license at gnu.org. */ package org.jboss.util; /** * Wait exclusive semaphore with wait - notify primitives * * @author <a href="mailto:simone.bordet@compaq.com">Simone Bordet</a> * @version $Revision: 1.1 $ */ public class WaitSemaphore extends Semaphore implements WaitSync { // Constants ----------------------------------------------------- private final static int MAX_USERS_ALLOWED = 1; // Attributes ---------------------------------------------------- private int m_waiters; // Static -------------------------------------------------------- // Constructors -------------------------------------------------- public WaitSemaphore() { super(MAX_USERS_ALLOWED); } // Public -------------------------------------------------------- public void doWait() throws InterruptedException { synchronized (this) { release(); ++m_waiters; waitImpl(this); --m_waiters; acquire(); } } public void doNotify() throws InterruptedException { synchronized (this) { if (getWaiters() > 0) { acquire(); notify(); release(); } } } public int getWaiters() { synchronized (this) { return m_waiters; } } // Object overrides --------------------------------------------------- public String toString() { return super.toString() + " - " + m_waiters; } // Package protected --------------------------------------------- // Protected ----------------------------------------------------- // Private ------------------------------------------------------- // Inner classes ------------------------------------------------- }
WaitSemaphore.java |