1 | // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
2 | // Use of this source code is governed by a BSD-style license that can be |
3 | // found in the LICENSE file. |
4 | |
5 | package org.chromium.net; |
6 | |
7 | import android.content.Context; |
8 | |
9 | import org.chromium.base.CalledByNative; |
10 | import org.chromium.base.JNINamespace; |
11 | import org.chromium.base.NativeClassQualifiedName; |
12 | import org.chromium.base.ObserverList; |
13 | |
14 | import java.util.ArrayList; |
15 | |
16 | /** |
17 | * Triggers updates to the underlying network state in Chrome. |
18 | * |
19 | * By default, connectivity is assumed and changes must pushed from the embedder via the |
20 | * forceConnectivityState function. |
21 | * Embedders may choose to have this class auto-detect changes in network connectivity by invoking |
22 | * the setAutoDetectConnectivityState function. |
23 | * |
24 | * WARNING: This class is not thread-safe. |
25 | */ |
26 | @JNINamespace("net") |
27 | public class NetworkChangeNotifier { |
28 | /** |
29 | * Alerted when the connection type of the network changes. |
30 | * The alert is fired on the UI thread. |
31 | */ |
32 | public interface ConnectionTypeObserver { |
33 | public void onConnectionTypeChanged(int connectionType); |
34 | } |
35 | |
36 | // These constants must always match the ones in network_change_notifier.h. |
37 | public static final int CONNECTION_UNKNOWN = 0; |
38 | public static final int CONNECTION_ETHERNET = 1; |
39 | public static final int CONNECTION_WIFI = 2; |
40 | public static final int CONNECTION_2G = 3; |
41 | public static final int CONNECTION_3G = 4; |
42 | public static final int CONNECTION_4G = 5; |
43 | public static final int CONNECTION_NONE = 6; |
44 | |
45 | private final Context mContext; |
46 | private final ArrayList<Integer> mNativeChangeNotifiers; |
47 | private final ObserverList<ConnectionTypeObserver> mConnectionTypeObservers; |
48 | private NetworkChangeNotifierAutoDetect mAutoDetector; |
49 | private int mCurrentConnectionType = CONNECTION_UNKNOWN; |
50 | |
51 | private static NetworkChangeNotifier sInstance; |
52 | |
53 | private NetworkChangeNotifier(Context context) { |
54 | mContext = context; |
55 | mNativeChangeNotifiers = new ArrayList<Integer>(); |
56 | mConnectionTypeObservers = new ObserverList<ConnectionTypeObserver>(); |
57 | } |
58 | |
59 | /** |
60 | * Initializes the singleton once. |
61 | */ |
62 | @CalledByNative |
63 | public static NetworkChangeNotifier init(Context context) { |
64 | if (sInstance == null) { |
65 | sInstance = new NetworkChangeNotifier(context); |
66 | } |
67 | return sInstance; |
68 | } |
69 | |
70 | public static boolean isInitialized() { |
71 | return sInstance != null; |
72 | } |
73 | |
74 | static void resetInstanceForTests(Context context) { |
75 | sInstance = new NetworkChangeNotifier(context); |
76 | } |
77 | |
78 | @CalledByNative |
79 | public int getCurrentConnectionType() { |
80 | return mCurrentConnectionType; |
81 | } |
82 | |
83 | /** |
84 | * Adds a native-side observer. |
85 | */ |
86 | @CalledByNative |
87 | public void addNativeObserver(int nativeChangeNotifier) { |
88 | mNativeChangeNotifiers.add(nativeChangeNotifier); |
89 | } |
90 | |
91 | /** |
92 | * Removes a native-side observer. |
93 | */ |
94 | @CalledByNative |
95 | public void removeNativeObserver(int nativeChangeNotifier) { |
96 | // Please keep the cast performing the boxing below. It ensures that the right method |
97 | // overload is used. ArrayList<T> has both remove(int index) and remove(T element). |
98 | mNativeChangeNotifiers.remove((Integer) nativeChangeNotifier); |
99 | } |
100 | |
101 | /** |
102 | * Returns the singleton instance. |
103 | */ |
104 | public static NetworkChangeNotifier getInstance() { |
105 | assert sInstance != null; |
106 | return sInstance; |
107 | } |
108 | |
109 | /** |
110 | * Enables auto detection of the current network state based on notifications from the system. |
111 | * Note that passing true here requires the embedding app have the platform ACCESS_NETWORK_STATE |
112 | * permission. |
113 | * |
114 | * @param shouldAutoDetect true if the NetworkChangeNotifier should listen for system changes in |
115 | * network connectivity. |
116 | */ |
117 | public static void setAutoDetectConnectivityState(boolean shouldAutoDetect) { |
118 | getInstance().setAutoDetectConnectivityStateInternal(shouldAutoDetect); |
119 | } |
120 | |
121 | private void destroyAutoDetector() { |
122 | if (mAutoDetector != null) { |
123 | mAutoDetector.destroy(); |
124 | mAutoDetector = null; |
125 | } |
126 | } |
127 | |
128 | private void setAutoDetectConnectivityStateInternal(boolean shouldAutoDetect) { |
129 | if (shouldAutoDetect) { |
130 | if (mAutoDetector == null) { |
131 | mAutoDetector = new NetworkChangeNotifierAutoDetect( |
132 | new NetworkChangeNotifierAutoDetect.Observer() { |
133 | @Override |
134 | public void onConnectionTypeChanged(int newConnectionType) { |
135 | updateCurrentConnectionType(newConnectionType); |
136 | } |
137 | }, |
138 | mContext); |
139 | mCurrentConnectionType = mAutoDetector.getCurrentConnectionType(); |
140 | } |
141 | } else { |
142 | destroyAutoDetector(); |
143 | } |
144 | } |
145 | |
146 | /** |
147 | * Updates the perceived network state when not auto-detecting changes to connectivity. |
148 | * |
149 | * @param networkAvailable True if the NetworkChangeNotifier should perceive a "connected" |
150 | * state, false implies "disconnected". |
151 | */ |
152 | @CalledByNative |
153 | public static void forceConnectivityState(boolean networkAvailable) { |
154 | setAutoDetectConnectivityState(false); |
155 | getInstance().forceConnectivityStateInternal(networkAvailable); |
156 | } |
157 | |
158 | private void forceConnectivityStateInternal(boolean forceOnline) { |
159 | boolean connectionCurrentlyExists = mCurrentConnectionType != CONNECTION_NONE; |
160 | if (connectionCurrentlyExists != forceOnline) { |
161 | updateCurrentConnectionType(forceOnline ? CONNECTION_UNKNOWN : CONNECTION_NONE); |
162 | } |
163 | } |
164 | |
165 | private void updateCurrentConnectionType(int newConnectionType) { |
166 | mCurrentConnectionType = newConnectionType; |
167 | notifyObserversOfConnectionTypeChange(newConnectionType); |
168 | } |
169 | |
170 | /** |
171 | * Alerts all observers of a connection change. |
172 | */ |
173 | void notifyObserversOfConnectionTypeChange(int newConnectionType) { |
174 | for (Integer nativeChangeNotifier : mNativeChangeNotifiers) { |
175 | nativeNotifyConnectionTypeChanged(nativeChangeNotifier, newConnectionType); |
176 | } |
177 | for (ConnectionTypeObserver observer : mConnectionTypeObservers) { |
178 | observer.onConnectionTypeChanged(newConnectionType); |
179 | } |
180 | } |
181 | |
182 | /** |
183 | * Adds an observer for any connection type changes. |
184 | */ |
185 | public static void addConnectionTypeObserver(ConnectionTypeObserver observer) { |
186 | getInstance().addConnectionTypeObserverInternal(observer); |
187 | } |
188 | |
189 | private void addConnectionTypeObserverInternal(ConnectionTypeObserver observer) { |
190 | if (!mConnectionTypeObservers.hasObserver(observer)) { |
191 | mConnectionTypeObservers.addObserver(observer); |
192 | } |
193 | } |
194 | |
195 | /** |
196 | * Removes an observer for any connection type changes. |
197 | */ |
198 | public static void removeConnectionTypeObserver(ConnectionTypeObserver observer) { |
199 | getInstance().removeConnectionTypeObserverInternal(observer); |
200 | } |
201 | |
202 | private void removeConnectionTypeObserverInternal(ConnectionTypeObserver observer) { |
203 | mConnectionTypeObservers.removeObserver(observer); |
204 | } |
205 | |
206 | @NativeClassQualifiedName("NetworkChangeNotifierDelegateAndroid") |
207 | private native void nativeNotifyConnectionTypeChanged(int nativePtr, int newConnectionType); |
208 | |
209 | @NativeClassQualifiedName("NetworkChangeNotifierDelegateAndroid") |
210 | private native int nativeGetConnectionType(int nativePtr); |
211 | |
212 | // For testing only. |
213 | public static NetworkChangeNotifierAutoDetect getAutoDetectorForTest() { |
214 | return getInstance().mAutoDetector; |
215 | } |
216 | |
217 | /** |
218 | * Checks if there currently is connectivity. |
219 | */ |
220 | public static boolean isOnline() { |
221 | int connectionType = getInstance().getCurrentConnectionType(); |
222 | return connectionType != CONNECTION_UNKNOWN && connectionType != CONNECTION_NONE; |
223 | } |
224 | } |