Add an API to check availability of Ethernet interface.

Bug: 18045481
Change-Id: I95358241b431cfe4435ce70c23c9a639b9dc4d58

core/java/android/net/EthernetManager.java

@@ -18,11 +18,14 @@ package android.net;
 
 import android.content.Context;
 import android.net.IEthernetManager;
+import android.net.IEthernetServiceListener;
 import android.net.IpConfiguration;
-import android.net.IpConfiguration.IpAssignment;
-import android.net.IpConfiguration.ProxySettings;
+import android.os.Handler;
+import android.os.Message;
 import android.os.RemoteException;
 
+import java.util.ArrayList;
+
 /**
  * A class representing the IP configuration of the Ethernet network.
  *
@@ -30,9 +33,41 @@ import android.os.RemoteException;
  */
 public class EthernetManager {
     private static final String TAG = "EthernetManager";
+    private static final int MSG_AVAILABILITY_CHANGED = 1000;
 
     private final Context mContext;
     private final IEthernetManager mService;
+    private final Handler mHandler = new Handler() {
+        @Override
+        public void handleMessage(Message msg) {
+            if (msg.what == MSG_AVAILABILITY_CHANGED) {
+                boolean isAvailable = (msg.arg1 == 1);
+                for (Listener listener : mListeners) {
+                    listener.onAvailabilityChanged(isAvailable);
+                }
+            }
+        }
+    };
+    private final ArrayList<Listener> mListeners = new ArrayList<Listener>();
+    private final IEthernetServiceListener.Stub mServiceListener =
+            new IEthernetServiceListener.Stub() {
+                @Override
+                public void onAvailabilityChanged(boolean isAvailable) {
+                    mHandler.obtainMessage(
+                            MSG_AVAILABILITY_CHANGED, isAvailable ? 1 : 0, 0, null).sendToTarget();
+                }
+            };
+
+    /**
+     * A listener interface to receive notification on changes in Ethernet.
+     */
+    public interface Listener {
+        /**
+         * Called when Ethernet port's availability is changed.
+         * @param isAvailable {@code true} if one or more Ethernet port exists.
+         */
+        public void onAvailabilityChanged(boolean isAvailable);
+    }
 
     /**
      * Create a new EthernetManager instance.
@@ -50,12 +85,9 @@ public class EthernetManager {
      * @return the Ethernet Configuration, contained in {@link IpConfiguration}.
      */
     public IpConfiguration getConfiguration() {
-        if (mService == null) {
-            return new IpConfiguration();
-        }
         try {
             return mService.getConfiguration();
-        } catch (RemoteException e) {
+        } catch (NullPointerException | RemoteException e) {
             return new IpConfiguration();
         }
     }
@@ -64,12 +96,57 @@ public class EthernetManager {
      * Set Ethernet configuration.
      */
     public void setConfiguration(IpConfiguration config) {
-        if (mService == null) {
-            return;
-        }
         try {
             mService.setConfiguration(config);
-        } catch (RemoteException e) {
+        } catch (NullPointerException | RemoteException e) {
+        }
+    }
+
+    /**
+     * Indicates whether the system currently has one or more
+     * Ethernet interfaces.
+     */
+    public boolean isAvailable() {
+        try {
+            return mService.isAvailable();
+        } catch (NullPointerException | RemoteException e) {
+            return false;
+        }
+    }
+
+    /**
+     * Adds a listener.
+     * @param listener A {@link Listener} to add.
+     * @throws IllegalArgumentException If the listener is null.
+     */
+    public void addListener(Listener listener) {
+        if (listener == null) {
+            throw new IllegalArgumentException("listener must not be null");
+        }
+        mListeners.add(listener);
+        if (mListeners.size() == 1) {
+            try {
+                mService.addListener(mServiceListener);
+            } catch (NullPointerException | RemoteException e) {
+            }
+        }
+    }
+
+    /**
+     * Removes a listener.
+     * @param listener A {@link Listener} to remove.
+     * @throws IllegalArgumentException If the listener is null.
+     */
+    public void removeListener(Listener listener) {
+        if (listener == null) {
+            throw new IllegalArgumentException("listener must not be null");
+        }
+        mListeners.remove(listener);
+        if (mListeners.isEmpty()) {
+            try {
+                mService.removeListener(mServiceListener);
+            } catch (NullPointerException | RemoteException e) {
+            }
         }
     }
 }

core/java/android/net/IEthernetManager.aidl

@@ -17,6 +17,7 @@
 package android.net;
 
 import android.net.IpConfiguration;
+import android.net.IEthernetServiceListener;
 
 /**
  * Interface that answers queries about, and allows changing
@@ -27,4 +28,7 @@ interface IEthernetManager
 {
     IpConfiguration getConfiguration();
     void setConfiguration(in IpConfiguration config);
+    boolean isAvailable();
+    void addListener(in IEthernetServiceListener listener);
+    void removeListener(in IEthernetServiceListener listener);
 }

core/java/android/net/IEthernetServiceListener.aidl

@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net;
+
+/** @hide */
+oneway interface IEthernetServiceListener
+{
+    void onAvailabilityChanged(boolean isAvailable);
+}