| 1 | // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | package org.chromium.base.test.util; |
| 6 | |
| 7 | import android.os.Handler; |
| 8 | import android.os.Looper; |
| 9 | |
| 10 | import java.util.concurrent.atomic.AtomicBoolean; |
| 11 | |
| 12 | /** |
| 13 | * This class is usefull when writing instrumentation tests that exercise code that posts tasks |
| 14 | * (to the same thread). |
| 15 | * Since the test code is run in a single thread, the posted tasks are never executed. |
| 16 | * The TestThread class lets you run that code on a specific thread synchronously and flush the |
| 17 | * message loop on that thread. |
| 18 | * |
| 19 | * Example of test using this: |
| 20 | * |
| 21 | * public void testMyAwesomeClass() { |
| 22 | * TestThread testThread = new TestThread(); |
| 23 | * testThread.startAndWaitForReadyState(); |
| 24 | * |
| 25 | * testThread.runOnTestThreadSyncAndProcessPendingTasks(new Runnable() { |
| 26 | * @Override |
| 27 | * public void run() { |
| 28 | * MyAwesomeClass.doStuffAsync(); |
| 29 | * } |
| 30 | * }); |
| 31 | * // Once we get there we know doStuffAsync has been executed and all the tasks it posted. |
| 32 | * assertTrue(MyAwesomeClass.stuffWasDone()); |
| 33 | * } |
| 34 | * |
| 35 | * Notes: |
| 36 | * - this is only for tasks posted to the same thread. Anyway if you were posting to a different |
| 37 | * thread, you'd probably need to set that other thread up. |
| 38 | * - this only supports tasks posted using Handler.post(), it won't work with postDelayed and |
| 39 | * postAtTime. |
| 40 | * - if your test instanciates an object and that object is the one doing the posting of tasks, you |
| 41 | * probably want to instanciate it on the test thread as it might create the Handler it posts |
| 42 | * tasks to in the constructor. |
| 43 | */ |
| 44 | |
| 45 | public class TestThread extends Thread { |
| 46 | private Object mThreadReadyLock; |
| 47 | private AtomicBoolean mThreadReady; |
| 48 | private Handler mMainThreadHandler; |
| 49 | private Handler mTestThreadHandler; |
| 50 | |
| 51 | public TestThread() { |
| 52 | mMainThreadHandler = new Handler(); |
| 53 | // We can't use the AtomicBoolean as the lock or findbugs will freak out... |
| 54 | mThreadReadyLock = new Object(); |
| 55 | mThreadReady = new AtomicBoolean(); |
| 56 | } |
| 57 | |
| 58 | @Override |
| 59 | public void run() { |
| 60 | Looper.prepare(); |
| 61 | mTestThreadHandler = new Handler(); |
| 62 | mTestThreadHandler.post(new Runnable() { |
| 63 | @Override |
| 64 | public void run() { |
| 65 | synchronized (mThreadReadyLock) { |
| 66 | mThreadReady.set(true); |
| 67 | mThreadReadyLock.notify(); |
| 68 | } |
| 69 | } |
| 70 | }); |
| 71 | Looper.loop(); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Starts this TestThread and blocks until it's ready to accept calls. |
| 76 | */ |
| 77 | public void startAndWaitForReadyState() { |
| 78 | checkOnMainThread(); |
| 79 | start(); |
| 80 | synchronized (mThreadReadyLock) { |
| 81 | try { |
| 82 | // Note the mThreadReady and while are not really needed. |
| 83 | // There are there so findbugs don't report warnings. |
| 84 | while (!mThreadReady.get()) { |
| 85 | mThreadReadyLock.wait(); |
| 86 | } |
| 87 | } catch (InterruptedException ie) { |
| 88 | System.err.println("Error starting TestThread."); |
| 89 | ie.printStackTrace(); |
| 90 | } |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | /** |
| 95 | * Runs the passed Runnable synchronously on the TestThread and returns when all pending |
| 96 | * runnables have been excuted. |
| 97 | * Should be called from the main thread. |
| 98 | */ |
| 99 | public void runOnTestThreadSyncAndProcessPendingTasks(Runnable r) { |
| 100 | checkOnMainThread(); |
| 101 | |
| 102 | runOnTestThreadSync(r); |
| 103 | |
| 104 | // Run another task, when it's done it means all pendings tasks have executed. |
| 105 | runOnTestThreadSync(null); |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Runs the passed Runnable on the test thread and blocks until it has finished executing. |
| 110 | * Should be called from the main thread. |
| 111 | * @param r The runnable to be executed. |
| 112 | */ |
| 113 | public void runOnTestThreadSync(final Runnable r) { |
| 114 | checkOnMainThread(); |
| 115 | final Object lock = new Object(); |
| 116 | // Task executed is not really needed since we are only on one thread, it is here to appease |
| 117 | // findbugs. |
| 118 | final AtomicBoolean taskExecuted = new AtomicBoolean(); |
| 119 | mTestThreadHandler.post(new Runnable() { |
| 120 | @Override |
| 121 | public void run() { |
| 122 | if (r != null) r.run(); |
| 123 | synchronized (lock) { |
| 124 | taskExecuted.set(true); |
| 125 | lock.notify(); |
| 126 | } |
| 127 | } |
| 128 | }); |
| 129 | synchronized (lock) { |
| 130 | try { |
| 131 | while (!taskExecuted.get()) { |
| 132 | lock.wait(); |
| 133 | } |
| 134 | } catch (InterruptedException ie) { |
| 135 | ie.printStackTrace(); |
| 136 | } |
| 137 | } |
| 138 | } |
| 139 | |
| 140 | private void checkOnMainThread() { |
| 141 | assert Looper.myLooper() == mMainThreadHandler.getLooper(); |
| 142 | } |
| 143 | } |