1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/mobile/android/base/util/ThreadUtils.java Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,200 @@
1.4 +/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
1.5 + * This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this file,
1.7 + * You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +package org.mozilla.gecko.util;
1.10 +
1.11 +import java.util.Map;
1.12 +
1.13 +import android.os.Handler;
1.14 +import android.os.MessageQueue;
1.15 +import android.util.Log;
1.16 +
1.17 +public final class ThreadUtils {
1.18 + private static final String LOGTAG = "ThreadUtils";
1.19 +
1.20 + /**
1.21 + * Controls the action taken when a method like
1.22 + * {@link ThreadUtils#assertOnUiThread(AssertBehavior)} detects a problem.
1.23 + */
1.24 + public static enum AssertBehavior {
1.25 + NONE,
1.26 + THROW,
1.27 + }
1.28 +
1.29 + private static volatile Thread sUiThread;
1.30 + private static volatile Thread sBackgroundThread;
1.31 +
1.32 + private static Handler sUiHandler;
1.33 +
1.34 + // Referenced directly from GeckoAppShell in highly performance-sensitive code (The extra
1.35 + // function call of the getter was harming performance. (Bug 897123))
1.36 + // Once Bug 709230 is resolved we should reconsider this as ProGuard should be able to optimise
1.37 + // this out at compile time.
1.38 + public static Handler sGeckoHandler;
1.39 + public static MessageQueue sGeckoQueue;
1.40 + public static Thread sGeckoThread;
1.41 +
1.42 + // Delayed Runnable that resets the Gecko thread priority.
1.43 + private static final Runnable sPriorityResetRunnable = new Runnable() {
1.44 + @Override
1.45 + public void run() {
1.46 + resetGeckoPriority();
1.47 + }
1.48 + };
1.49 +
1.50 + private static boolean sIsGeckoPriorityReduced;
1.51 +
1.52 + @SuppressWarnings("serial")
1.53 + public static class UiThreadBlockedException extends RuntimeException {
1.54 + public UiThreadBlockedException() {
1.55 + super();
1.56 + }
1.57 +
1.58 + public UiThreadBlockedException(String msg) {
1.59 + super(msg);
1.60 + }
1.61 +
1.62 + public UiThreadBlockedException(String msg, Throwable e) {
1.63 + super(msg, e);
1.64 + }
1.65 +
1.66 + public UiThreadBlockedException(Throwable e) {
1.67 + super(e);
1.68 + }
1.69 + }
1.70 +
1.71 + public static void dumpAllStackTraces() {
1.72 + Log.w(LOGTAG, "Dumping ALL the threads!");
1.73 + Map<Thread, StackTraceElement[]> allStacks = Thread.getAllStackTraces();
1.74 + for (Thread t : allStacks.keySet()) {
1.75 + Log.w(LOGTAG, t.toString());
1.76 + for (StackTraceElement ste : allStacks.get(t)) {
1.77 + Log.w(LOGTAG, ste.toString());
1.78 + }
1.79 + Log.w(LOGTAG, "----");
1.80 + }
1.81 + }
1.82 +
1.83 + public static void setUiThread(Thread thread, Handler handler) {
1.84 + sUiThread = thread;
1.85 + sUiHandler = handler;
1.86 + }
1.87 +
1.88 + public static void setBackgroundThread(Thread thread) {
1.89 + sBackgroundThread = thread;
1.90 + }
1.91 +
1.92 + public static Thread getUiThread() {
1.93 + return sUiThread;
1.94 + }
1.95 +
1.96 + public static Handler getUiHandler() {
1.97 + return sUiHandler;
1.98 + }
1.99 +
1.100 + public static void postToUiThread(Runnable runnable) {
1.101 + sUiHandler.post(runnable);
1.102 + }
1.103 +
1.104 + public static Thread getBackgroundThread() {
1.105 + return sBackgroundThread;
1.106 + }
1.107 +
1.108 + public static Handler getBackgroundHandler() {
1.109 + return GeckoBackgroundThread.getHandler();
1.110 + }
1.111 +
1.112 + public static void postToBackgroundThread(Runnable runnable) {
1.113 + GeckoBackgroundThread.post(runnable);
1.114 + }
1.115 +
1.116 + public static void assertOnUiThread(final AssertBehavior assertBehavior) {
1.117 + assertOnThread(getUiThread(), assertBehavior);
1.118 + }
1.119 +
1.120 + public static void assertOnUiThread() {
1.121 + assertOnThread(getUiThread(), AssertBehavior.THROW);
1.122 + }
1.123 +
1.124 + public static void assertOnGeckoThread() {
1.125 + assertOnThread(sGeckoThread, AssertBehavior.THROW);
1.126 + }
1.127 +
1.128 + public static void assertOnBackgroundThread() {
1.129 + assertOnThread(getBackgroundThread(), AssertBehavior.THROW);
1.130 + }
1.131 +
1.132 + public static void assertOnThread(final Thread expectedThread) {
1.133 + assertOnThread(expectedThread, AssertBehavior.THROW);
1.134 + }
1.135 +
1.136 + public static void assertOnThread(final Thread expectedThread, AssertBehavior behavior) {
1.137 + final Thread currentThread = Thread.currentThread();
1.138 + final long currentThreadId = currentThread.getId();
1.139 + final long expectedThreadId = expectedThread.getId();
1.140 +
1.141 + if (currentThreadId == expectedThreadId) {
1.142 + return;
1.143 + }
1.144 +
1.145 + final String message = "Expected thread " +
1.146 + expectedThreadId + " (\"" + expectedThread.getName() +
1.147 + "\"), but running on thread " +
1.148 + currentThreadId + " (\"" + currentThread.getName() + ")";
1.149 + final IllegalThreadStateException e = new IllegalThreadStateException(message);
1.150 +
1.151 + switch (behavior) {
1.152 + case THROW:
1.153 + throw e;
1.154 + default:
1.155 + Log.e(LOGTAG, "Method called on wrong thread!", e);
1.156 + }
1.157 + }
1.158 +
1.159 + public static boolean isOnUiThread() {
1.160 + return isOnThread(getUiThread());
1.161 + }
1.162 +
1.163 + public static boolean isOnBackgroundThread() {
1.164 + if (sBackgroundThread == null) {
1.165 + return false;
1.166 + }
1.167 +
1.168 + return isOnThread(sBackgroundThread);
1.169 + }
1.170 +
1.171 + public static boolean isOnThread(Thread thread) {
1.172 + return (Thread.currentThread().getId() == thread.getId());
1.173 + }
1.174 +
1.175 + /**
1.176 + * Reduces the priority of the Gecko thread, allowing other operations
1.177 + * (such as those related to the UI and database) to take precedence.
1.178 + *
1.179 + * Note that there are no guards in place to prevent multiple calls
1.180 + * to this method from conflicting with each other.
1.181 + *
1.182 + * @param timeout Timeout in ms after which the priority will be reset
1.183 + */
1.184 + public static void reduceGeckoPriority(long timeout) {
1.185 + if (!sIsGeckoPriorityReduced) {
1.186 + sIsGeckoPriorityReduced = true;
1.187 + sGeckoThread.setPriority(Thread.MIN_PRIORITY);
1.188 + getUiHandler().postDelayed(sPriorityResetRunnable, timeout);
1.189 + }
1.190 + }
1.191 +
1.192 + /**
1.193 + * Resets the priority of a thread whose priority has been reduced
1.194 + * by reduceGeckoPriority.
1.195 + */
1.196 + public static void resetGeckoPriority() {
1.197 + if (sIsGeckoPriorityReduced) {
1.198 + sIsGeckoPriorityReduced = false;
1.199 + sGeckoThread.setPriority(Thread.NORM_PRIORITY);
1.200 + getUiHandler().removeCallbacks(sPriorityResetRunnable);
1.201 + }
1.202 + }
1.203 +}
