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.util; 18 19 import android.os.AsyncTask; 20 import android.os.Looper; 21 22 import com.android.contacts.common.testing.NeededForTesting; 23 import com.google.common.base.Preconditions; 24 25 import java.util.concurrent.Executor; 26 27 /** 28 * Factory methods for creating AsyncTaskExecutors. 29 * <p> 30 * All of the factory methods on this class check first to see if you have set a static 31 * {@link AsyncTaskExecutorFactory} set through the 32 * {@link #setFactoryForTest(AsyncTaskExecutorFactory)} method, and if so delegate to that instead, 33 * which is one way of injecting dependencies for testing classes whose construction cannot be 34 * controlled such as {@link android.app.Activity}. 35 */ 36 public final class AsyncTaskExecutors { 37 /** 38 * A single instance of the {@link AsyncTaskExecutorFactory}, to which we delegate if it is 39 * non-null, for injecting when testing. 40 */ 41 private static AsyncTaskExecutorFactory mInjectedAsyncTaskExecutorFactory = null; 42 43 /** 44 * Creates an AsyncTaskExecutor that submits tasks to run with 45 * {@link AsyncTask#SERIAL_EXECUTOR}. 46 */ 47 public static AsyncTaskExecutor createAsyncTaskExecutor() { 48 synchronized (AsyncTaskExecutors.class) { 49 if (mInjectedAsyncTaskExecutorFactory != null) { 50 return mInjectedAsyncTaskExecutorFactory.createAsyncTaskExeuctor(); 51 } 52 return new SimpleAsyncTaskExecutor(AsyncTask.SERIAL_EXECUTOR); 53 } 54 } 55 56 /** 57 * Creates an AsyncTaskExecutor that submits tasks to run with 58 * {@link AsyncTask#THREAD_POOL_EXECUTOR}. 59 */ 60 public static AsyncTaskExecutor createThreadPoolExecutor() { 61 synchronized (AsyncTaskExecutors.class) { 62 if (mInjectedAsyncTaskExecutorFactory != null) { 63 return mInjectedAsyncTaskExecutorFactory.createAsyncTaskExeuctor(); 64 } 65 return new SimpleAsyncTaskExecutor(AsyncTask.THREAD_POOL_EXECUTOR); 66 } 67 } 68 69 /** Interface for creating AsyncTaskExecutor objects. */ 70 public interface AsyncTaskExecutorFactory { 71 AsyncTaskExecutor createAsyncTaskExeuctor(); 72 } 73 74 @NeededForTesting 75 public static void setFactoryForTest(AsyncTaskExecutorFactory factory) { 76 synchronized (AsyncTaskExecutors.class) { 77 mInjectedAsyncTaskExecutorFactory = factory; 78 } 79 } 80 81 public static void checkCalledFromUiThread() { 82 Preconditions.checkState(Thread.currentThread() == Looper.getMainLooper().getThread(), 83 "submit method must be called from ui thread, was: " + Thread.currentThread()); 84 } 85 86 private static class SimpleAsyncTaskExecutor implements AsyncTaskExecutor { 87 private final Executor mExecutor; 88 89 public SimpleAsyncTaskExecutor(Executor executor) { 90 mExecutor = executor; 91 } 92 93 @Override 94 public <T> AsyncTask<T, ?, ?> submit(Object identifer, AsyncTask<T, ?, ?> task, 95 T... params) { 96 checkCalledFromUiThread(); 97 return task.executeOnExecutor(mExecutor, params); 98 } 99 } 100 } 101
