| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * 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.android.contacts.util; |
| |
| import android.os.AsyncTask; |
| import android.os.Looper; |
| |
| import com.android.contacts.test.NeededForTesting; |
| import com.google.common.base.Preconditions; |
| |
| import java.util.concurrent.Executor; |
| |
| /** |
| * Factory methods for creating AsyncTaskExecutors. |
| * <p> |
| * All of the factory methods on this class check first to see if you have set a static |
| * {@link AsyncTaskExecutorFactory} set through the |
| * {@link #setFactoryForTest(AsyncTaskExecutorFactory)} method, and if so delegate to that instead, |
| * which is one way of injecting dependencies for testing classes whose construction cannot be |
| * controlled such as {@link android.app.Activity}. |
| */ |
| public final class AsyncTaskExecutors { |
| /** |
| * A single instance of the {@link AsyncTaskExecutorFactory}, to which we delegate if it is |
| * non-null, for injecting when testing. |
| */ |
| private static AsyncTaskExecutorFactory mInjectedAsyncTaskExecutorFactory = null; |
| |
| /** |
| * Creates an AsyncTaskExecutor that submits tasks to run with |
| * {@link AsyncTask#SERIAL_EXECUTOR}. |
| */ |
| public static AsyncTaskExecutor createAsyncTaskExecutor() { |
| synchronized (AsyncTaskExecutors.class) { |
| if (mInjectedAsyncTaskExecutorFactory != null) { |
| return mInjectedAsyncTaskExecutorFactory.createAsyncTaskExeuctor(); |
| } |
| return new SimpleAsyncTaskExecutor(AsyncTask.SERIAL_EXECUTOR); |
| } |
| } |
| |
| /** |
| * Creates an AsyncTaskExecutor that submits tasks to run with |
| * {@link AsyncTask#THREAD_POOL_EXECUTOR}. |
| */ |
| public static AsyncTaskExecutor createThreadPoolExecutor() { |
| synchronized (AsyncTaskExecutors.class) { |
| if (mInjectedAsyncTaskExecutorFactory != null) { |
| return mInjectedAsyncTaskExecutorFactory.createAsyncTaskExeuctor(); |
| } |
| return new SimpleAsyncTaskExecutor(AsyncTask.THREAD_POOL_EXECUTOR); |
| } |
| } |
| |
| /** Interface for creating AsyncTaskExecutor objects. */ |
| public interface AsyncTaskExecutorFactory { |
| AsyncTaskExecutor createAsyncTaskExeuctor(); |
| } |
| |
| @NeededForTesting |
| public static void setFactoryForTest(AsyncTaskExecutorFactory factory) { |
| synchronized (AsyncTaskExecutors.class) { |
| mInjectedAsyncTaskExecutorFactory = factory; |
| } |
| } |
| |
| public static void checkCalledFromUiThread() { |
| Preconditions.checkState(Thread.currentThread() == Looper.getMainLooper().getThread(), |
| "submit method must be called from ui thread, was: " + Thread.currentThread()); |
| } |
| |
| private static class SimpleAsyncTaskExecutor implements AsyncTaskExecutor { |
| private final Executor mExecutor; |
| |
| public SimpleAsyncTaskExecutor(Executor executor) { |
| mExecutor = executor; |
| } |
| |
| @Override |
| public <T> AsyncTask<T, ?, ?> submit(Object identifer, AsyncTask<T, ?, ?> task, |
| T... params) { |
| checkCalledFromUiThread(); |
| return task.executeOnExecutor(mExecutor, params); |
| } |
| } |
| } |