| /* |
| * 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 final 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(); |
| } |