/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.brooklyn.util.core.mutex;
/** interface which allows multiple callers to co-operate using named mutexes, inspectably,
* and containing implementation as inner class
* <p>
* MutexSupport is a common implementation of this.
* mixin code frequently delegates to this,
* as shown in the test case's WithMutexesTest.SampleWithMutexesDelegatingMixin class
**/
public interface WithMutexes {
/** returns true if the calling thread has the mutex with the given ID */
public boolean hasMutex(String mutexId);
/** acquires a mutex, if available, otherwise blocks on its becoming available;
* caller must release after use */
public void acquireMutex(String mutexId, String description) throws InterruptedException;
/** acquires a mutex and returns true, if available; otherwise immediately returns false;
* caller must release after use if this returns true */
public boolean tryAcquireMutex(String mutexId, String description);
/** releases a mutex, triggering another thread to use it or cleaning it up if no one else is waiting;
* this should only be called by the mutex owner (thread) */
public void releaseMutex(String mutexId);
}