Add NetworkChangeNotifier for Android.

net/android/java/org/chromium/net/NetworkChangeNotifier.java

Index: net/android/java/org/chromium/net/NetworkChangeNotifier.java
diff --git a/net/android/java/org/chromium/net/NetworkChangeNotifier.java b/net/android/java/org/chromium/net/NetworkChangeNotifier.java
new file mode 100644
index 0000000000000000000000000000000000000000..e21f61f78bd833176dac330eaa45ab8eee0dd730
--- /dev/null
+++ b/net/android/java/org/chromium/net/NetworkChangeNotifier.java
@@ -0,0 +1,129 @@
+// Copyright (c) 2012 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.net;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+import android.util.Log;
+
+import org.chromium.base.ActivityStatus;
+import org.chromium.base.CalledByNative;
+
+/**
+ * Triggers updates to the underlying network state in native Chrome
+ */
+public class NetworkChangeNotifier extends BroadcastReceiver implements ActivityStatus.Listener {
+
+    private static final String TAG = "NetworkChangeNotifier";
+
+    private final NetworkConnectivityIntentFilter mIntentFilter =
+            new NetworkConnectivityIntentFilter();
+
+    private Context mContext;
+    private int mNativeChangeNotifier;
+    private boolean mRegistered;
+    private boolean mIsConnected;
+
+    private static NetworkChangeNotifier sNetworkChangeNotifierForTest;
+
+    public static NetworkChangeNotifier getNetworkChangeNotifierForTest() {
+      return sNetworkChangeNotifierForTest;
+    }
+
+    private NetworkChangeNotifier(Context context, int nativeChangeNotifier) {
+        mContext = context;
+        mNativeChangeNotifier = nativeChangeNotifier;
+        mIsConnected = checkIfConnected(mContext);
+        ActivityStatus status = ActivityStatus.getInstance();
+        if (!status.isPaused()) {
+          registerReceiver();
+        }
+        status.registerListener(this);
+        sNetworkChangeNotifierForTest = this;
+    }
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        if (intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, false)) {
+            if (mIsConnected) {
+              mIsConnected = false;
+              Log.d(TAG, "Network connectivity changed, no connectivity.");
+              nativeNotifyObservers(mNativeChangeNotifier);
+            }
+        } else {
+            boolean isConnected = checkIfConnected(context);
+            if (isConnected != mIsConnected) {
+              mIsConnected = isConnected;
+              Log.d(TAG, "Network connectivity changed, status is: " + isConnected);
+              nativeNotifyObservers(mNativeChangeNotifier);
+            }
+        }
+    }
+
+    private boolean checkIfConnected(Context context) {
+      ConnectivityManager manager = (ConnectivityManager)
+              context.getSystemService(Context.CONNECTIVITY_SERVICE);
+      boolean isConnected = false;
+      for (NetworkInfo info: manager.getAllNetworkInfo()) {
+          if (info.isConnected()) {
+              isConnected = true;
+              break;
+          }
+      }
+      return isConnected;
+    }
+
+    @CalledByNative
+    private boolean isConnected() {
+      return mIsConnected;
+    }
+
+    /**
+     * Register a BroadcastReceiver in the given context.
+     */
+    private void registerReceiver() {
+        if (!mRegistered) {
+          mRegistered = true;
+          mContext.registerReceiver(this, mIntentFilter);
+        }
+    }
+    /**
+     * Unregister the BroadcastReceiver in the given context.
+     */
+    @CalledByNative
+    private void unregisterReceiver() {
+        if (mRegistered) {
+           mRegistered = false;
+           mContext.unregisterReceiver(this);
+        }
+    }
+
+    @Override
+    public void onActivityStatusChanged(boolean isPaused) {
+        if (isPaused) {
+            unregisterReceiver();
+        } else {
+            registerReceiver();
+        }
+    }
+
+    @CalledByNative
+    static NetworkChangeNotifier create(Context context, int nativeNetworkChangeNotifier) {
+        return new NetworkChangeNotifier(context, nativeNetworkChangeNotifier);
+    }
+
+    private static class NetworkConnectivityIntentFilter extends IntentFilter {
+      NetworkConnectivityIntentFilter() {
+          addAction(ConnectivityManager.CONNECTIVITY_ACTION);
+      }
+    }
+
+    private native void nativeNotifyObservers(
+        int nativeNetworkChangeNotifier /* net::android::NetworkChangeNotifier */);
+}