/*
* Copyright (C) 2015 DroidDriver committers
*
* 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 io.appium.droiddriver.helpers;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* Base class for an action that should run only once no matter how many times the method {@link
* #singleRun()} is called upon an instance. Typically it is used on a singleton to achieve once for
* a class effect.
*/
public abstract class SingleRun {
private AtomicBoolean hasRun = new AtomicBoolean();
/**
* Calls {@link #run()} if it is the first time this method is called upon this instance.
*
* @return true if this is the first time it is called, otherwise false
*/
public final boolean singleRun() {
if (hasRun.compareAndSet(false, true)) {
run();
return true;
}
return false;
}
/**
* Takes the action that should run only once.
*/
protected abstract void run();
}