Issue 5931 - Create tests for util package

adblockplussbrowser/src/main/java/org/adblockplus/sbrowser/contentblocker/engine/EngineService.java

Index: adblockplussbrowser/src/main/java/org/adblockplus/sbrowser/contentblocker/engine/EngineService.java
===================================================================
new file mode 100644
--- /dev/null
+++ b/adblockplussbrowser/src/main/java/org/adblockplus/sbrowser/contentblocker/engine/EngineService.java
@@ -0,0 +1,189 @@
+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-present eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.adblockplus.sbrowser.contentblocker.engine;
+
+import java.util.concurrent.LinkedBlockingQueue;
+
+import android.app.Service;
+import android.content.Context;
+import android.content.Intent;
+import android.os.IBinder;
+import android.util.Log;
+
+public final class EngineService extends Service
+{
+  private static final String TAG = EngineService.class.getSimpleName();
+
+  private volatile Engine engine = null;
+  private volatile boolean isInitialized = false;
+  private Throwable failureCause = null;
+  private static final LinkedBlockingQueue<EngineCreatedCallbackWrapper> ON_CREATED_CALLBACKS =
+      new LinkedBlockingQueue<>();
+
+  @Override
+  public int onStartCommand(Intent intent, int flags, int startId)
+  {
+    return Service.START_STICKY;
+  }
+
+  /**
+   * The callback gets executed on the UI thread.
+   *
+   * @param context
+   * @param callback
+   */
+  public static void startService(final Context context, final OnEngineCreatedCallback callback)
+  {
+    startService(context, callback, true);
+  }
+
+  /**
+   *
+   * @param context
+   * @param callback
+   * @param runOnUiThread
+   *          {@code true} if the callback should be executed on the UI thread
+   */
+  public static void startService(final Context context, final OnEngineCreatedCallback callback,
+      final boolean runOnUiThread)
+  {
+    context.startService(new Intent(context, EngineService.class));
+    ON_CREATED_CALLBACKS.offer(new EngineCreatedCallbackWrapper(callback, runOnUiThread));
+  }
+
+  @Override
+  public void onCreate()
+  {
+    super.onCreate();
+    startDaemonThread(new Initializer(this));
+    startDaemonThread(new CreationNotifier(this));
+  }
+
+  @Override
+  public IBinder onBind(Intent intent)
+  {
+    return null;
+  }
+
+  private static void startDaemonThread(final Runnable runnable)
+  {
+    final Thread t = new Thread(runnable);
+    t.setDaemon(true);
+    t.start();
+  }
+
+  private static class Initializer implements Runnable
+  {
+    private final EngineService service;
+
+    public Initializer(final EngineService service)
+    {
+      this.service = service;
+    }
+
+    @Override
+    public void run()
+    {
+      try
+      {
+        this.service.engine = Engine.create(this.service.getApplicationContext());
+      }
+      catch (Throwable t)
+      {
+        Log.e(TAG, "Initialization failed: " + t.getMessage(), t);
+        this.service.failureCause = t;
+      }
+      finally
+      {
+        this.service.isInitialized = true;
+      }
+    }
+  }
+
+  private static class CreationNotifier implements Runnable
+  {
+    private static final String TAG = CreationNotifier.class.getSimpleName();
+    private final EngineService service;
+
+    public CreationNotifier(final EngineService service)
+    {
+      this.service = service;
+    }
+
+    @Override
+    public void run()
+    {
+      try
+      {
+        while (!this.service.isInitialized)
+        {
+          Thread.sleep(250);
+        }
+
+        for (;;)
+        {
+          final EngineCreatedCallbackWrapper wrapper = EngineService.ON_CREATED_CALLBACKS.take();
+          if (wrapper != null)
+          {
+            if (wrapper.runOnUiThread)
+            {
+              Engine.runOnUiThread(new Runnable()
+              {
+                private final EngineService service = CreationNotifier.this.service;
+
+                @Override
+                public void run()
+                {
+                  wrapper.callback.onEngineCreated(this.service.engine,
+                      this.service.failureCause == null);
+                }
+              });
+            }
+            else
+            {
+              wrapper.callback.onEngineCreated(this.service.engine,
+                  this.service.failureCause == null);
+            }
+          }
+        }
+      }
+      catch (final Throwable t)
+      {
+        Log.e(TAG, "Notifier died: " + t.getMessage(), t);
+      }
+    }
+  }
+
+  public interface OnEngineCreatedCallback
+  {
+    void onEngineCreated(Engine engine, boolean success);
+  }
+
+  private static class EngineCreatedCallbackWrapper
+  {
+    final OnEngineCreatedCallback callback;
+    final boolean runOnUiThread;
+
+    public EngineCreatedCallbackWrapper(final OnEngineCreatedCallback callback,
+        final boolean runOnUiThread)
+    {
+      this.callback = callback;
+      this.runOnUiThread = runOnUiThread;
+    }
+  }
+}