aw: Move thread hop code to ProviderFactory

android_webview/glue/java/src/com/android/webview/chromium/WebViewChromiumFactoryProvider.java

 // Copyright 2014 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 com.android.webview.chromium;
 
 import android.Manifest;
 import android.app.ActivityManager;
 import android.content.ComponentCallbacks2;
 import android.content.Context;
@@ skipping 40 matching lines @@
 import org.chromium.base.TraceEvent;
 import org.chromium.base.annotations.SuppressFBWarnings;
 import org.chromium.base.library_loader.LibraryLoader;
 import org.chromium.base.library_loader.LibraryProcessType;
 import org.chromium.base.library_loader.ProcessInitException;
 import org.chromium.content.browser.ContentViewStatics;
 import org.chromium.net.NetworkChangeNotifier;
 import org.chromium.ui.base.ResourceBundle;
 
 import java.io.File;
-import java.lang.ref.WeakReference;
-import java.util.ArrayList;
+import java.util.Queue;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.FutureTask;
+import java.util.concurrent.TimeUnit;
 
 /**
  * Entry point to the WebView. The system framework talks to this class to get instances of the
  * implementation classes.
  */
 @SuppressWarnings("deprecation")
 public class WebViewChromiumFactoryProvider implements WebViewFactoryProvider {
     private static final String TAG = "WebViewChromiumFactoryProvider";
 
     private static final String CHROMIUM_PREFS_NAME = "WebViewChromiumPrefs";
     private static final String VERSION_CODE_PREF = "lastVersionCodeUsed";
     private static final String COMMAND_LINE_FILE = "/data/local/tmp/webview-command-line";
 
+    private class WebViewChromiumRunQueue {
+        public WebViewChromiumRunQueue() {
+            mQueue = new ConcurrentLinkedQueue<Runnable>();
+        }
+
+        public void addTask(Runnable task) {
+            mQueue.add(task);
+            if (WebViewChromiumFactoryProvider.this.hasStarted()) {
+                ThreadUtils.runOnUiThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        drainQueue();
+                    }
+                });
+            }
+        }
+
+        public void drainQueue() {
+            if (mQueue == null || mQueue.isEmpty()) {
+                return;
+            }
+
+            Runnable task = mQueue.poll();
+            while (task != null) {
+                task.run();
+                task = mQueue.poll();
+            }
+        }
+
+        private Queue<Runnable> mQueue;
+    }
+
+    private final WebViewChromiumRunQueue mRunQueue = new WebViewChromiumRunQueue();
+
+    private <T> T runBlockingFuture(FutureTask<T> task) {
+        if (!hasStarted()) throw new RuntimeException("Must be started before we block!");
+        if (ThreadUtils.runningOnUiThread()) {
+            throw new IllegalStateException("This method should only be called off the UI thread");
+        }
+        mRunQueue.addTask(task);
+        try {
+            return task.get(4, TimeUnit.SECONDS);
+        } catch (java.util.concurrent.TimeoutException e) {
+            throw new RuntimeException("Probable deadlock detected due to WebView API being called "
+                            + "on incorrect thread while the UI thread is blocked.", e);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    // We have a 4 second timeout to try to detect deadlocks to detect and aid in debuggin
+    // deadlocks.
+    // Do not call this method while on the UI thread!
+    /* package */ void runVoidTaskOnUiThreadBlocking(Runnable r) {
+        FutureTask<Void> task = new FutureTask<Void>(r, null);
+        runBlockingFuture(task);
+    }
+
+    /* package */ <T> T runOnUiThreadBlocking(Callable<T> c) {
+        return runBlockingFuture(new FutureTask<T>(c));
+    }
+
+    /* package */ void addTask(Runnable task) {
+        mRunQueue.addTask(task);
+    }
+
     // Guards accees to the other members, and is notifyAll() signalled on the UI thread
     // when the chromium process has been started.
     private final Object mLock = new Object();
 
     // Initialization guarded by mLock.
     private AwBrowserContext mBrowserContext;
     private Statics mStaticMethods;
     private GeolocationPermissionsAdapter mGeolocationPermissions;
     private CookieManagerAdapter mCookieManager;
     private WebIconDatabaseAdapter mWebIconDatabase;
     private WebStorageAdapter mWebStorage;
     private WebViewDatabaseAdapter mWebViewDatabase;
     private AwDevToolsServer mDevToolsServer;
 
-    private ArrayList<WeakReference<WebViewChromium>> mWebViewsToStart =
-            new ArrayList<WeakReference<WebViewChromium>>();
-
     // Read/write protected by mLock.
     private boolean mStarted;
 
     private SharedPreferences mWebViewPrefs;
     private WebViewDelegate mWebViewDelegate;
 
     /**
      * Constructor called by the API 21 version of {@link WebViewFactory} and earlier.
      */
     public WebViewChromiumFactoryProvider() {
@@ skipping 190 matching lines @@
 
         TraceEvent.setATraceEnabled(mWebViewDelegate.isTraceTagEnabled());
         mWebViewDelegate.setOnTraceEnabledChangeListener(
                 new WebViewDelegate.OnTraceEnabledChangeListener() {
                     @Override
                     public void onTraceEnabledChange(boolean enabled) {
                         TraceEvent.setATraceEnabled(enabled);
                     }
                 });
         mStarted = true;
-
-        for (WeakReference<WebViewChromium> wvc : mWebViewsToStart) {
-            WebViewChromium w = wvc.get();
-            if (w != null) {
-                w.startYourEngine();
-            }
-        }
-        mWebViewsToStart.clear();
-        mWebViewsToStart = null;
+        mRunQueue.drainQueue();
     }
 
     boolean hasStarted() {
         return mStarted;
     }
 
     void startYourEngines(boolean onMainThread) {
         synchronized (mLock) {
             ensureChromiumStartedLocked(onMainThread);
         }
@@ skipping 86 matching lines @@
                         return AwContentsClient.parseFileChooserResult(resultCode, intent);
                     }
                 };
             }
         }
         return mStaticMethods;
     }
 
     @Override
     public WebViewProvider createWebView(WebView webView, WebView.PrivateAccess privateAccess) {
-        WebViewChromium wvc = new WebViewChromium(this, webView, privateAccess);
-
-        synchronized (mLock) {
-            if (mWebViewsToStart != null) {
-                mWebViewsToStart.add(new WeakReference<WebViewChromium>(wvc));
-            }
-        }
-
-        return wvc;
+        return new WebViewChromium(this, webView, privateAccess);
     }
 
     @Override
     public GeolocationPermissions getGeolocationPermissions() {
         synchronized (mLock) {
             if (mGeolocationPermissions == null) {
                 ensureChromiumStartedLocked(true);
                 mGeolocationPermissions = new GeolocationPermissionsAdapter(
                         getBrowserContextLocked().getGeolocationPermissions());
             }
@@ skipping 43 matching lines @@
                         browserContext.getHttpAuthDatabase(context));
             }
         }
         return mWebViewDatabase;
     }
 
     WebViewDelegate getWebViewDelegate() {
         return mWebViewDelegate;
     }
 }