Upstream oodles of Chrome for Android code into Chromium.

chrome/android/java_staging/src/org/chromium/chrome/browser/gcore/ConnectedTask.java

+// Copyright 2015 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.chrome.browser.gcore;
+
+import org.chromium.base.Log;
+import org.chromium.base.TraceEvent;
+import org.chromium.base.VisibleForTesting;
+import org.chromium.base.annotations.NoSideEffects;
+
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Base class for tasks which connects to Google Play Services using given GoogleApiClient,
+ * performs action specified in doWhenConnected method, disconnects the client and cleans up
+ * by invoking cleanUp method.
+ *
+ * <p>
+ * Using the same client for tasks running in more than one thread is a serious error, as
+ * the state can then be modified while other threads are still using the client. The
+ * recommended way to use these tasks is with a {@link java.util.concurrent.ThreadPoolExecutor}
+ * having a pool size of 1.
+ * </p>
+ * <p>
+ * This class waits {@link #CONNECTION_TIMEOUT_MS} milliseconds for connection to be established.
+ * If connection is unsuccessful then it will retry after {@link #CONNECTION_RETRY_TIME_MS}
+ * milliseconds as long as Google Play Services is available. Number of retries is limited to
+ * {@link #RETRY_NUMBER_LIMIT}.
+ * </p>
+ *
+ * @param <T> type of {@link ChromeGoogleApiClient} to use for the tasks
+ */
+public abstract class ConnectedTask<T extends ChromeGoogleApiClient> implements Runnable {
+    private static final String TAG = Log.makeTag("GCore");
+
+    public static final long CONNECTION_TIMEOUT_MS = TimeUnit.SECONDS.toMillis(5);
+    public static final long CONNECTION_RETRY_TIME_MS = TimeUnit.SECONDS.toMillis(10);
+    public static final int RETRY_NUMBER_LIMIT = 5;
+
+    private final T mClient;
+    private int mRetryNumber;
+
+    /**
+     * Used for logging and tracing.
+     * <ul>
+     * <li>Log format: "{logPrefix}| {{@link #getName()}} {message}"</li>
+     * <li>Trace format: "ConnectedTask:{logPrefix}:{traceEventName}"</li>
+     * </ul>
+     */
+    private final String mLogPrefix;
+
+    /**
+     * @param client
+     * @param logPrefix used for logging and tracing.
+     */
+    public ConnectedTask(T client, String logPrefix) {
+        assert logPrefix != null;
+        mClient = client;
+        mLogPrefix = logPrefix;
+    }
+
+    /** Creates a connected task with an empty log prefix. */
+    @VisibleForTesting
+    public ConnectedTask(T client) {
+        this(client, "");
+    }
+
+    /**
+     * Executed with client connected to Google Play Services.
+     * This method is intended to be overridden by a subclass.
+     */
+    protected abstract void doWhenConnected(T client);
+
+    /**
+     * Returns a name of a task. Implementations should not have side effects
+     * as we want to have the logging related calls removed.
+     */
+    @NoSideEffects
+    protected abstract String getName();
+
+    /**
+     * Executed after doWhenConnected was done and client was disconnected.
+     * May also be executed when Google Play Services is no longer available, which means connection
+     * was unsuccessful and won't be retried.
+     * This method is intended to be overridden by a subclass.
+     */
+    protected void cleanUp() {}
+
+    /**
+     * Executed if the connection was unsuccessful.
+     * This method is intended to be overridden by a subclass.
+     */
+    protected void connectionFailed() {}
+
+    @Override
+    @VisibleForTesting
+    public final void run() {
+        TraceEvent.begin("GCore:" + mLogPrefix + ":run");
+        try {
+            Log.d(TAG, "%s:%s started", mLogPrefix, getName());
+            if (mClient.connectWithTimeout(CONNECTION_TIMEOUT_MS)) {
+                try {
+                    Log.d(TAG, "%s:%s connected", mLogPrefix, getName());
+                    doWhenConnected(mClient);
+                    Log.d(TAG, "%s:%s finished", mLogPrefix, getName());
+                } finally {
+                    mClient.disconnect();
+                    Log.d(TAG, "%s:%s disconnected", mLogPrefix, getName());
+                    cleanUp();
+                    Log.d(TAG, "%s:%s cleaned up", mLogPrefix, getName());
+                }
+            } else {
+                mRetryNumber++;
+                if (mRetryNumber < RETRY_NUMBER_LIMIT && mClient.isGooglePlayServicesAvailable()) {
+                    Log.d(TAG, "%s:%s calling retry", mLogPrefix, getName());
+                    retry(this, CONNECTION_RETRY_TIME_MS);
+                } else {
+                    connectionFailed();
+                    Log.d(TAG, "%s:%s number of retries exceeded", mLogPrefix, getName());
+                    cleanUp();
+                    Log.d(TAG, "%s:%s cleaned up", mLogPrefix, getName());
+                }
+            }
+        } catch (RuntimeException e) {
+            Log.e(TAG, "%s:%s runtime exception %s: %s", mLogPrefix, getName(),
+                    e.getClass().getName(), e.getMessage());
+            throw e;
+        } finally {
+            TraceEvent.end("GCore:" + mLogPrefix + ":run");
+        }
+    }
+
+    /** Method to implement to determine how to run the retry task. */
+    protected abstract void retry(Runnable task, long delayMs);
+}