ModernAsyncTask.java revision ea85d97d6a7eed3aedbde96bbeb40690599ef071
1fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn/* 28a2ca60963f77938e1a611f2342ad043dc9467cfDianne Hackborn * Copyright (C) 2011 The Android Open Source Project 3fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 4fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Licensed under the Apache License, Version 2.0 (the "License"); 5fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * you may not use this file except in compliance with the License. 6fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * You may obtain a copy of the License at 7fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 8fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * http://www.apache.org/licenses/LICENSE-2.0 9fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 10fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Unless required by applicable law or agreed to in writing, software 11fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * distributed under the License is distributed on an "AS IS" BASIS, 12fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * See the License for the specific language governing permissions and 14fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * limitations under the License. 15fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 16fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 17fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornpackage android.support.v4.content; 18fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 19fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.BlockingQueue; 20fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.Callable; 21fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.CancellationException; 22fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.ExecutionException; 23fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.Executor; 24fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.FutureTask; 25fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.LinkedBlockingQueue; 26fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.ThreadFactory; 27fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.ThreadPoolExecutor; 28fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.TimeUnit; 29fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.TimeoutException; 30fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.atomic.AtomicBoolean; 31fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport java.util.concurrent.atomic.AtomicInteger; 32fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 33ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brownimport android.os.AsyncTask; 34fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport android.os.Handler; 35ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brownimport android.os.Looper; 36fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport android.os.Message; 37fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackbornimport android.os.Process; 38fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 39fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn/** 400574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * Copy of the required parts of {@link android.os.AsyncTask} from Android 3.0 that is 410574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * needed to support AsyncTaskLoader. We use this rather than the one from the platform 42fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * because we rely on some subtle behavior of AsyncTask that is not reliable on 43fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * older platforms. 447dc96cc2410f551eefaa973ddc144146ad72d1ecDianne Hackborn * 457dc96cc2410f551eefaa973ddc144146ad72d1ecDianne Hackborn * <p>Note that for now this is not publicly available because it is not a 467dc96cc2410f551eefaa973ddc144146ad72d1ecDianne Hackborn * complete implementation, only sufficient for the needs of 477dc96cc2410f551eefaa973ddc144146ad72d1ecDianne Hackborn * {@link AsyncTaskLoader}. 48fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 497dc96cc2410f551eefaa973ddc144146ad72d1ecDianne Hackbornabstract class ModernAsyncTask<Params, Progress, Result> { 50fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final String LOG_TAG = "AsyncTask"; 51fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 52fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final int CORE_POOL_SIZE = 5; 53fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final int MAXIMUM_POOL_SIZE = 128; 54fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final int KEEP_ALIVE = 1; 55fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 56fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final ThreadFactory sThreadFactory = new ThreadFactory() { 57fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private final AtomicInteger mCount = new AtomicInteger(1); 58fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 59fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public Thread newThread(Runnable r) { 60fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return new Thread(r, "ModernAsyncTask #" + mCount.getAndIncrement()); 61fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 62fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn }; 63fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 64fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final BlockingQueue<Runnable> sPoolWorkQueue = 65fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn new LinkedBlockingQueue<Runnable>(10); 66fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 67fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 68fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * An {@link Executor} that can be used to execute tasks in parallel. 69fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 70fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public static final Executor THREAD_POOL_EXECUTOR 71fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn = new ThreadPoolExecutor(CORE_POOL_SIZE, MAXIMUM_POOL_SIZE, KEEP_ALIVE, 72fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn TimeUnit.SECONDS, sPoolWorkQueue, sThreadFactory); 73fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 74fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final int MESSAGE_POST_RESULT = 0x1; 75fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static final int MESSAGE_POST_PROGRESS = 0x2; 76fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 77ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown private static InternalHandler sHandler; 78fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 79fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static volatile Executor sDefaultExecutor = THREAD_POOL_EXECUTOR; 80fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private final WorkerRunnable<Params, Result> mWorker; 81fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private final FutureTask<Result> mFuture; 82fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 83fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private volatile Status mStatus = Status.PENDING; 84fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 85fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private final AtomicBoolean mTaskInvoked = new AtomicBoolean(); 86fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 87fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 88fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Indicates the current status of the task. Each status will be set only once 89fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * during the lifetime of a task. 90fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 91fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public enum Status { 92fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 93fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Indicates that the task has not been executed yet. 94fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 95fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn PENDING, 96fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 97fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Indicates that the task is running. 98fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 99fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn RUNNING, 100fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 1010574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * Indicates that {@link android.os.AsyncTask#onPostExecute(Object)} has finished. 102fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 103fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn FINISHED, 104fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 105fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 106ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown private static Handler getHandler() { 107ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown synchronized (AsyncTask.class) { 108ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown if (sHandler == null) { 109ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown sHandler = new InternalHandler(); 110ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown } 111ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown return sHandler; 112ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown } 113fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 114fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 115fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** @hide */ 116fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public static void setDefaultExecutor(Executor exec) { 117fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn sDefaultExecutor = exec; 118fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 119fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 120fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 121fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Creates a new asynchronous task. This constructor must be invoked on the UI thread. 122fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 123fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public ModernAsyncTask() { 124fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mWorker = new WorkerRunnable<Params, Result>() { 125fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public Result call() throws Exception { 126fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mTaskInvoked.set(true); 127fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 128fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND); 129fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return postResult(doInBackground(mParams)); 130fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 131fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn }; 132fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 133fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mFuture = new FutureTask<Result>(mWorker) { 134fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn @Override 135fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected void done() { 136fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn try { 137fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn final Result result = get(); 138fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 139fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn postResultIfNotInvoked(result); 140fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } catch (InterruptedException e) { 141fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn android.util.Log.w(LOG_TAG, e); 142fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } catch (ExecutionException e) { 143c3be3233cd98f3017af981313ec6af24d3ab7f43Adrian Roos throw new RuntimeException( 144c3be3233cd98f3017af981313ec6af24d3ab7f43Adrian Roos "An error occurred while executing doInBackground()", e.getCause()); 145fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } catch (CancellationException e) { 146fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn postResultIfNotInvoked(null); 147fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } catch (Throwable t) { 148c3be3233cd98f3017af981313ec6af24d3ab7f43Adrian Roos throw new RuntimeException( 149c3be3233cd98f3017af981313ec6af24d3ab7f43Adrian Roos "An error occurred while executing doInBackground()", t); 150fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 151fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 152fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn }; 153fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 154fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 155fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private void postResultIfNotInvoked(Result result) { 156fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn final boolean wasTaskInvoked = mTaskInvoked.get(); 157fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn if (!wasTaskInvoked) { 158fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn postResult(result); 159fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 160fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 161fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 162fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private Result postResult(Result result) { 163ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown Message message = getHandler().obtainMessage(MESSAGE_POST_RESULT, 164fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn new AsyncTaskResult<Result>(this, result)); 165fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn message.sendToTarget(); 166fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return result; 167fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 168fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 169fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 170fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Returns the current status of this task. 171fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 172fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return The current status. 173fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 174fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public final Status getStatus() { 175fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return mStatus; 176fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 177fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 178fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 179fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Override this method to perform a computation on a background thread. The 180fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * specified parameters are the parameters passed to {@link #execute} 181fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * by the caller of this task. 182fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 183fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * This method can call {@link #publishProgress} to publish updates 184fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * on the UI thread. 185fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 186fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param params The parameters of the task. 187fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 188fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return A result, defined by the subclass of this task. 189fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 190fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onPreExecute() 191fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onPostExecute 192fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #publishProgress 193fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 194fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected abstract Result doInBackground(Params... params); 195fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 196fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 197fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Runs on the UI thread before {@link #doInBackground}. 198fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 199fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onPostExecute 200fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #doInBackground 201fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 202fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected void onPreExecute() { 203fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 204fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 205fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 206fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>Runs on the UI thread after {@link #doInBackground}. The 207fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * specified result is the value returned by {@link #doInBackground}.</p> 208fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 209fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>This method won't be invoked if the task was cancelled.</p> 210fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 211fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param result The result of the operation computed by {@link #doInBackground}. 212fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 213fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onPreExecute 214fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #doInBackground 215fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onCancelled(Object) 216fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 217fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn @SuppressWarnings({"UnusedDeclaration"}) 218fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected void onPostExecute(Result result) { 219fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 220fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 221fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 222fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Runs on the UI thread after {@link #publishProgress} is invoked. 223fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * The specified values are the values passed to {@link #publishProgress}. 224fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 225fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param values The values indicating progress. 226fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 227fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #publishProgress 228fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #doInBackground 229fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 230fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn @SuppressWarnings({"UnusedDeclaration"}) 231fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected void onProgressUpdate(Progress... values) { 232fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 233fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 234fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 235fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>Runs on the UI thread after {@link #cancel(boolean)} is invoked and 236fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #doInBackground(Object[])} has finished.</p> 237fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 238fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>The default implementation simply invokes {@link #onCancelled()} and 239fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * ignores the result. If you write your own implementation, do not call 240fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <code>super.onCancelled(result)</code>.</p> 241fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 242fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param result The result, if any, computed in 243fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #doInBackground(Object[])}, can be null 244fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 245fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #cancel(boolean) 246fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #isCancelled() 247fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 248fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn @SuppressWarnings({"UnusedParameters"}) 249fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected void onCancelled(Result result) { 250fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn onCancelled(); 251fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 252fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 253fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 254fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>Applications should preferably override {@link #onCancelled(Object)}. 255fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * This method is invoked by the default implementation of 256fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #onCancelled(Object)}.</p> 257fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 258fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>Runs on the UI thread after {@link #cancel(boolean)} is invoked and 259fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #doInBackground(Object[])} has finished.</p> 260fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 261fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onCancelled(Object) 262fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #cancel(boolean) 263fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #isCancelled() 264fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 265fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected void onCancelled() { 266fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 267fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 268fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 269fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Returns <tt>true</tt> if this task was cancelled before it completed 270fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * normally. If you are calling {@link #cancel(boolean)} on the task, 271fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * the value returned by this method should be checked periodically from 272fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #doInBackground(Object[])} to end the task as soon as possible. 273fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 274fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return <tt>true</tt> if task was cancelled before it completed 275fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 276fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #cancel(boolean) 277fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 278fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public final boolean isCancelled() { 279fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return mFuture.isCancelled(); 280fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 281fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 282fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 283fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>Attempts to cancel execution of this task. This attempt will 284fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * fail if the task has already completed, already been cancelled, 285fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * or could not be cancelled for some other reason. If successful, 286fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * and this task has not started when <tt>cancel</tt> is called, 287fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * this task should never run. If the task has already started, 288fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * then the <tt>mayInterruptIfRunning</tt> parameter determines 289fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * whether the thread executing this task should be interrupted in 290fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * an attempt to stop the task.</p> 291fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 292fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>Calling this method will result in {@link #onCancelled(Object)} being 293fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * invoked on the UI thread after {@link #doInBackground(Object[])} 294fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * returns. Calling this method guarantees that {@link #onPostExecute(Object)} 295fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * is never invoked. After invoking this method, you should check the 296fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * value returned by {@link #isCancelled()} periodically from 297fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #doInBackground(Object[])} to finish the task as early as 298fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * possible.</p> 299fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 300fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param mayInterruptIfRunning <tt>true</tt> if the thread executing this 301fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * task should be interrupted; otherwise, in-progress tasks are allowed 302fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * to complete. 303fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 304fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return <tt>false</tt> if the task could not be cancelled, 305fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * typically because it has already completed normally; 306fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <tt>true</tt> otherwise 307fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 308fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #isCancelled() 309fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onCancelled(Object) 310fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 311fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public final boolean cancel(boolean mayInterruptIfRunning) { 312fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return mFuture.cancel(mayInterruptIfRunning); 313fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 314fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 315fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 316fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Waits if necessary for the computation to complete, and then 317fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * retrieves its result. 318fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 319fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return The computed result. 320fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 321fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws CancellationException If the computation was cancelled. 322fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws ExecutionException If the computation threw an exception. 323fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws InterruptedException If the current thread was interrupted 324fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * while waiting. 325fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 326fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public final Result get() throws InterruptedException, ExecutionException { 327fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return mFuture.get(); 328fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 329fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 330fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 331fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Waits if necessary for at most the given time for the computation 332fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * to complete, and then retrieves its result. 333fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 334fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param timeout Time to wait before cancelling the operation. 335fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param unit The time unit for the timeout. 336fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 337fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return The computed result. 338fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 339fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws CancellationException If the computation was cancelled. 340fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws ExecutionException If the computation threw an exception. 341fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws InterruptedException If the current thread was interrupted 342fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * while waiting. 343fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws TimeoutException If the wait timed out. 344fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 345fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public final Result get(long timeout, TimeUnit unit) throws InterruptedException, 346fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn ExecutionException, TimeoutException { 347fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return mFuture.get(timeout, unit); 348fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 349fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 350fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 351fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Executes the task with the specified parameters. The task returns 352fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * itself (this) so that the caller can keep a reference to it. 353fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 354fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>Note: this function schedules the task on a queue for a single background 355fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * thread or pool of threads depending on the platform version. When first 356fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * introduced, AsyncTasks were executed serially on a single background thread. 357fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Starting with {@link android.os.Build.VERSION_CODES#DONUT}, this was changed 358fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * to a pool of threads allowing multiple tasks to operate in parallel. After 359fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link android.os.Build.VERSION_CODES#HONEYCOMB}, it is planned to change this 360fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * back to a single thread to avoid common application errors caused 361fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * by parallel execution. If you truly want parallel execution, you can use 362fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * the {@link #executeOnExecutor} version of this method 363fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * with {@link #THREAD_POOL_EXECUTOR}; however, see commentary there for warnings on 364fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * its use. 365fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 366fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>This method must be invoked on the UI thread. 367fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 368fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param params The parameters of the task. 369fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 370fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return This instance of AsyncTask. 371fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 372fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws IllegalStateException If {@link #getStatus()} returns either 3730574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * {@link android.os.AsyncTask.Status#RUNNING} or 3740574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * {@link android.os.AsyncTask.Status#FINISHED}. 375fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 376fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public final ModernAsyncTask<Params, Progress, Result> execute(Params... params) { 377fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return executeOnExecutor(sDefaultExecutor, params); 378fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 379fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 380fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 381fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Executes the task with the specified parameters. The task returns 382fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * itself (this) so that the caller can keep a reference to it. 383fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 384fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>This method is typically used with {@link #THREAD_POOL_EXECUTOR} to 385fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * allow multiple tasks to run in parallel on a pool of threads managed by 386fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * AsyncTask, however you can also use your own {@link Executor} for custom 387fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * behavior. 388fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 389fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p><em>Warning:</em> Allowing multiple tasks to run in parallel from 390fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * a thread pool is generally <em>not</em> what one wants, because the order 391fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * of their operation is not defined. For example, if these tasks are used 392fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * to modify any state in common (such as writing a file due to a button click), 393fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * there are no guarantees on the order of the modifications. 394fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Without careful work it is possible in rare cases for the newer version 395fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * of the data to be over-written by an older one, leading to obscure data 3960574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * loss and stability issues. 397fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 398fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * <p>This method must be invoked on the UI thread. 399fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 400fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param exec The executor to use. {@link #THREAD_POOL_EXECUTOR} is available as a 401fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * convenient process-wide thread pool for tasks that are loosely coupled. 402fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param params The parameters of the task. 403fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 404fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @return This instance of AsyncTask. 405fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 406fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @throws IllegalStateException If {@link #getStatus()} returns either 4070574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * {@link android.os.AsyncTask.Status#RUNNING} 4080574ca37da4619afe4e26753f5a1b4de314b6565Svetoslav Ganov * or {@link android.os.AsyncTask.Status#FINISHED}. 409fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 410fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public final ModernAsyncTask<Params, Progress, Result> executeOnExecutor(Executor exec, 411fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn Params... params) { 412fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn if (mStatus != Status.PENDING) { 413fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn switch (mStatus) { 414fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn case RUNNING: 415fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn throw new IllegalStateException("Cannot execute task:" 416fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn + " the task is already running."); 417fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn case FINISHED: 418fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn throw new IllegalStateException("Cannot execute task:" 419fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn + " the task has already been executed " 420fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn + "(a task can be executed only once)"); 421fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 422fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 423fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 424fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mStatus = Status.RUNNING; 425fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 426fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn onPreExecute(); 427fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 428fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mWorker.mParams = params; 429fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn exec.execute(mFuture); 430fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 431fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn return this; 432fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 433fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 434fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 435fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * Convenience version of {@link #execute(Object...)} for use with 436fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * a simple Runnable object. 437fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 438fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public static void execute(Runnable runnable) { 439fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn sDefaultExecutor.execute(runnable); 440fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 441fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 442fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn /** 443fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * This method can be invoked from {@link #doInBackground} to 444fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * publish updates on the UI thread while the background computation is 445fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * still running. Each call to this method will trigger the execution of 446fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #onProgressUpdate} on the UI thread. 447fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 448fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * {@link #onProgressUpdate} will note be called if the task has been 449fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * canceled. 450fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 451fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @param values The progress values to update the UI with. 452fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * 453fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #onProgressUpdate 454fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn * @see #doInBackground 455fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn */ 456fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn protected final void publishProgress(Progress... values) { 457fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn if (!isCancelled()) { 458ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown getHandler().obtainMessage(MESSAGE_POST_PROGRESS, 459fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn new AsyncTaskResult<Progress>(this, values)).sendToTarget(); 460fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 461fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 462fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 463fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private void finish(Result result) { 464fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn if (isCancelled()) { 465fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn onCancelled(result); 466fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } else { 467fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn onPostExecute(result); 468fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 469fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mStatus = Status.FINISHED; 470fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 471fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 472fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static class InternalHandler extends Handler { 473ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown public InternalHandler() { 474ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown super(Looper.getMainLooper()); 475ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown } 476ea85d97d6a7eed3aedbde96bbeb40690599ef071Jeff Brown 477fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn @SuppressWarnings({"unchecked", "RawUseOfParameterizedType"}) 478fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn @Override 479fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn public void handleMessage(Message msg) { 480fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn AsyncTaskResult result = (AsyncTaskResult) msg.obj; 481fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn switch (msg.what) { 482fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn case MESSAGE_POST_RESULT: 483fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn // There is only one result 484fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn result.mTask.finish(result.mData[0]); 485fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn break; 486fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn case MESSAGE_POST_PROGRESS: 487fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn result.mTask.onProgressUpdate(result.mData); 488fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn break; 489fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 490fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 491fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 492fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 493fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static abstract class WorkerRunnable<Params, Result> implements Callable<Result> { 494fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn Params[] mParams; 495fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 496fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 497fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn @SuppressWarnings({"RawUseOfParameterizedType"}) 498fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn private static class AsyncTaskResult<Data> { 499fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn final ModernAsyncTask mTask; 500fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn final Data[] mData; 501fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn 502fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn AsyncTaskResult(ModernAsyncTask task, Data... data) { 503fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mTask = task; 504fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn mData = data; 505fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 506fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn } 507fbabff99ccbcb576c713991c5db5dec21a0d0ce0Dianne Hackborn} 508