1 /* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.dialer.common.concurrent; 18 19 import android.os.AsyncTask; 20 import android.support.annotation.MainThread; 21 import com.android.dialer.common.Assert; 22 import java.util.concurrent.Executor; 23 24 /** 25 * Factory methods for creating AsyncTaskExecutors. 26 * 27 * <p>All of the factory methods on this class check first to see if you have set a static {@link 28 * AsyncTaskExecutorFactory} set through the {@link #setFactoryForTest(AsyncTaskExecutorFactory)} 29 * method, and if so delegate to that instead, which is one way of injecting dependencies for 30 * testing classes whose construction cannot be controlled such as {@link android.app.Activity}. 31 */ 32 public final class AsyncTaskExecutors { 33 34 /** 35 * A single instance of the {@link AsyncTaskExecutorFactory}, to which we delegate if it is 36 * non-null, for injecting when testing. 37 */ 38 private static AsyncTaskExecutorFactory injectedAsyncTaskExecutorFactory = null; 39 40 /** 41 * Creates an AsyncTaskExecutor that submits tasks to run with {@link AsyncTask#SERIAL_EXECUTOR}. 42 */ createAsyncTaskExecutor()43 public static AsyncTaskExecutor createAsyncTaskExecutor() { 44 synchronized (AsyncTaskExecutors.class) { 45 if (injectedAsyncTaskExecutorFactory != null) { 46 return injectedAsyncTaskExecutorFactory.createAsyncTaskExeuctor(); 47 } 48 return new SimpleAsyncTaskExecutor(AsyncTask.SERIAL_EXECUTOR); 49 } 50 } 51 52 /** 53 * Creates an AsyncTaskExecutor that submits tasks to run with {@link 54 * AsyncTask#THREAD_POOL_EXECUTOR}. 55 */ createThreadPoolExecutor()56 public static AsyncTaskExecutor createThreadPoolExecutor() { 57 synchronized (AsyncTaskExecutors.class) { 58 if (injectedAsyncTaskExecutorFactory != null) { 59 return injectedAsyncTaskExecutorFactory.createAsyncTaskExeuctor(); 60 } 61 return new SimpleAsyncTaskExecutor(AsyncTask.THREAD_POOL_EXECUTOR); 62 } 63 } 64 setFactoryForTest(AsyncTaskExecutorFactory factory)65 public static void setFactoryForTest(AsyncTaskExecutorFactory factory) { 66 synchronized (AsyncTaskExecutors.class) { 67 injectedAsyncTaskExecutorFactory = factory; 68 } 69 } 70 71 /** Interface for creating AsyncTaskExecutor objects. */ 72 public interface AsyncTaskExecutorFactory { 73 createAsyncTaskExeuctor()74 AsyncTaskExecutor createAsyncTaskExeuctor(); 75 } 76 77 static class SimpleAsyncTaskExecutor implements AsyncTaskExecutor { 78 79 private final Executor executor; 80 SimpleAsyncTaskExecutor(Executor executor)81 public SimpleAsyncTaskExecutor(Executor executor) { 82 this.executor = executor; 83 } 84 85 @Override 86 @MainThread submit(Object identifer, AsyncTask<T, ?, ?> task, T... params)87 public <T> AsyncTask<T, ?, ?> submit(Object identifer, AsyncTask<T, ?, ?> task, T... params) { 88 Assert.isMainThread(); 89 return task.executeOnExecutor(executor, params); 90 } 91 } 92 } 93