Upstream Android Geolocation

content/android/java/org/chromium/content/browser/ThreadUtils.java

Index: content/android/java/org/chromium/content/browser/ThreadUtils.java
diff --git a/content/android/java/org/chromium/content/browser/ThreadUtils.java b/content/android/java/org/chromium/content/browser/ThreadUtils.java
new file mode 100644
index 0000000000000000000000000000000000000000..cce87fa8cc6d03ab18a2e73af0ca4780b713a1d5
--- /dev/null
+++ b/content/android/java/org/chromium/content/browser/ThreadUtils.java
@@ -0,0 +1,134 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.content.browser;
+
+import android.os.Handler;
+import android.os.Looper;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.FutureTask;
+
+/**
+ * Helper methods to deal with threading related tasks.
+ */
+public class ThreadUtils {
+
+    /**
+     * Run the supplied Runnable on the main thread. The method will block until
+     * the Runnable completes.
+     *
+     * @param r The Runnable to run.
+     */
+    public static void runOnUiThreadBlocking(final Runnable r) {
+        if (runningOnUiThread()) {
+            r.run();
+        } else {
+            FutureTask<Void> task = new FutureTask<Void>(r, null);
+            postOnUiThread(task);
+            try {
+                task.get();
+            } catch (Exception e) {
+                throw new RuntimeException("Exception occured while waiting for runnable", e);
+            }
+        }
+    }
+
+    /**
+     * Run the supplied Callable on the main thread, wrapping any exceptions in
+     * a RuntimeException. The method will block until the Callable completes.
+     *
+     * @param c The Callable to run
+     * @return The result of the callable
+     */
+    public static <T> T runOnUiThreadBlockingNoException(Callable<T> c) {
+        try {
+            return runOnUiThreadBlocking(c);
+        } catch (ExecutionException e) {
+            throw new RuntimeException("Error occured waiting for callable", e);
+        }
+    }
+
+    /**
+     * Run the supplied Callable on the main thread, The method will block until
+     * the Callable completes.
+     *
+     * @param c The Callable to run
+     * @return The result of the callable
+     * @throws ExecutionException c's exception
+     */
+    public static <T> T runOnUiThreadBlocking(Callable<T> c) throws ExecutionException {
+        FutureTask<T> task = new FutureTask<T>(c);
+        runOnUiThread(task);
+        try {
+            return task.get();
+        } catch (InterruptedException e) {
+            throw new RuntimeException("Interrupted waiting for callable", e);
+        }
+    }
+
+    /**
+     * Run the supplied FutureTask on the main thread. The method will block
+     * only if the current thread is the main thread.
+     *
+     * @param task The FutureTask to run
+     * @return The queried task (to aid inline construction)
+     */
+    public static <T> FutureTask<T> runOnUiThread(FutureTask<T> task) {
+        if (runningOnUiThread()) {
+            task.run();
+        } else {
+            postOnUiThread(task);
+        }
+        return task;
+    }
+
+    /**
+     * Run the supplied Callable on the main thread. The method will block
+     * only if the current thread is the main thread.
+     *
+     * @param c The Callable to run
+     * @return A FutureTask wrapping the callable to retrieve results
+     */
+    public static <T> FutureTask<T> runOnUiThread(Callable<T> c) {
+        return runOnUiThread(new FutureTask<T>(c));
+    }
+
+    /**
+     * Run the supplied Runnable on the main thread. The method will block
+     * only if the current thread is the main thread.
+     *
+     * @param r The Runnable to run
+     */
+    public static void runOnUiThread(Runnable r) {
+        runOnUiThread(new FutureTask<Void>(r, null));
+    }
+
+    /**
+     * Post the supplied FutureTask to run on the main thread. The method will
+     * not block, even if called on the UI thread.
+     *
+     * @param task The FutureTask to run
+     * @return The queried task (to aid inline construction)
+     */
+    public static <T> FutureTask<T> postOnUiThread(FutureTask<T> task) {
+        new Handler(Looper.getMainLooper()).post(task);
+        return task;
+    }
+
+    /**
+     * Asserts that the current thread is running on the main thread.
+     */
+    public static void assertOnUiThread() {
+        assert runningOnUiThread();
+    }
+
+    /**
+     * @return true iff the current thread is the main (UI) thread.
+     */
+    public static boolean runningOnUiThread() {
+      return Looper.getMainLooper() == Looper.myLooper();
+    }
+}