/** * Copyright 2011 JogAmp Community. All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, are * permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this list of * conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, this list * of conditions and the following disclaimer in the documentation and/or other materials * provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * The views and conclusions contained in the software and documentation are those of the * authors and should not be interpreted as representing official policies, either expressed * or implied, of JogAmp Community. */ package com.jogamp.common.util.locks; /** * Reentrance capable locking toolkit, supporting multiple threads as owner. *

* See use case description at {@link #addOwner(Thread)}. *

*/ public interface RecursiveThreadGroupLock extends RecursiveLock { /** * Returns true if the current thread is the original lock owner, ie. * successfully claimed this lock the first time, ie. {@link #getHoldCount()} == 1. */ boolean isOriginalOwner(); /** * Returns true if the passed thread is the original lock owner, ie. * successfully claimed this lock the first time, ie. {@link #getHoldCount()} == 1. */ boolean isOriginalOwner(Thread thread); /** * Add a thread to the list of additional lock owners, which enables them to recursively claim this lock. *

* The caller must hold this lock and be the original lock owner, see {@link #isOriginalOwner()}. *

*

* If the original owner releases this lock via {@link #unlock()} * all additional lock owners are released as well. * This ensures consistency of spawn off additional lock owner threads and it's release. *

* Use case: *
     * Thread2 thread2 = new Thread2();
     * 
     * Thread1 {
     * 
     *   // Claim this lock and become the original lock owner.
     *   lock.lock();
     *   
     *   try {
     *   
     *     // Allow Thread2 to claim the lock, ie. make thread2 an additional lock owner
     *     addOwner(thread2);
     *     
     *     // Start thread2
     *     thread2.start();
     *     
     *     // Wait until thread2 has finished requiring this lock, but keep thread2 running
     *     while(!thread2.waitForResult()) sleep(); 
     *     
     *     // Optional: Only if sure that this thread doesn't hold the lock anymore,
     *     // otherwise just release the lock via unlock(). 
     *     removeOwner(thread2);
     *     
     *   } finally {
     *   
     *     // Release this lock and remove all additional lock owners.
     *     // Implicit wait until thread2 gets off the lock.
     *     lock.unlock();
     *     
     *   }
     *   
     * }.start();
     * 
* * @param t the thread to be added to the list of additional owning threads * @throws RuntimeException if the current thread does not hold the lock. * @throws IllegalArgumentException if the passed thread is the lock owner or already added. * * @see #removeOwner(Thread) * @see #unlock() * @see #lock() */ void addOwner(Thread t) throws RuntimeException, IllegalArgumentException; /** * Remove a thread from the list of additional lock owner threads. *

* The caller must hold this lock and be the original lock owner, see {@link #isOriginalOwner()}. *

*

* Only use this method if sure that the thread doesn't hold the lock anymore. *

* * @param t the thread to be removed from the list of additional owning threads * @throws RuntimeException if the current thread does not hold the lock. * @throws IllegalArgumentException if the passed thread is not added by {@link #addOwner(Thread)} */ void removeOwner(Thread t) throws RuntimeException, IllegalArgumentException; /** *

* Wait's until all additional owners released this lock before releasing it. *

* * {@inheritDoc} */ @Override void unlock() throws RuntimeException; /** *

* Wait's until all additional owners released this lock before releasing it. *

* * {@inheritDoc} */ @Override void unlock(Runnable taskAfterUnlockBeforeNotify); }