/*
* Copyright 2000-2012 JetBrains s.r.o.
*
* Licensed 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 com.intellij.concurrency;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* Executes given runnable exactly once.
*
* Author: dmitrylomov
*/
public class DoOnce {
private Runnable myRunnable;
private final AtomicBoolean myAlreadyRun;
public DoOnce(Runnable runnable) {
myRunnable = runnable;
myAlreadyRun = new AtomicBoolean(false);
}
public void execute() {
if (myAlreadyRun.compareAndSet(false, true)) {
try {
myRunnable.run();
} finally {
myRunnable = null; // do not leak runnable
}
}
}
}