1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.support.v4.net;
18
19import static android.net.ConnectivityManager.TYPE_MOBILE;
20import static android.net.ConnectivityManager.TYPE_WIFI;
21
22import android.content.Intent;
23import android.net.ConnectivityManager;
24import android.net.NetworkInfo;
25import android.os.Build;
26
27/**
28 * Helper for accessing features in {@link ConnectivityManager} introduced after
29 * API level 16 in a backwards compatible fashion.
30 */
31public class ConnectivityManagerCompat {
32
33    interface ConnectivityManagerCompatImpl {
34        boolean isActiveNetworkMetered(ConnectivityManager cm);
35    }
36
37    static class BaseConnectivityManagerCompatImpl implements ConnectivityManagerCompatImpl {
38        @Override
39        public boolean isActiveNetworkMetered(ConnectivityManager cm) {
40            final NetworkInfo info = cm.getActiveNetworkInfo();
41            if (info == null) {
42                // err on side of caution
43                return true;
44            }
45
46            final int type = info.getType();
47            switch (type) {
48                case TYPE_MOBILE:
49                    return true;
50                case TYPE_WIFI:
51                    return false;
52                default:
53                    // err on side of caution
54                    return true;
55            }
56        }
57    }
58
59    static class GingerbreadConnectivityManagerCompatImpl implements ConnectivityManagerCompatImpl {
60        @Override
61        public boolean isActiveNetworkMetered(ConnectivityManager cm) {
62            return ConnectivityManagerCompatGingerbread.isActiveNetworkMetered(cm);
63        }
64    }
65
66    static class HoneycombMR2ConnectivityManagerCompatImpl
67            implements ConnectivityManagerCompatImpl {
68        @Override
69        public boolean isActiveNetworkMetered(ConnectivityManager cm) {
70            return ConnectivityManagerCompatHoneycombMR2.isActiveNetworkMetered(cm);
71        }
72    }
73
74    static class JellyBeanConnectivityManagerCompatImpl implements ConnectivityManagerCompatImpl {
75        @Override
76        public boolean isActiveNetworkMetered(ConnectivityManager cm) {
77            return ConnectivityManagerCompatJellyBean.isActiveNetworkMetered(cm);
78        }
79    }
80
81    private static final ConnectivityManagerCompatImpl IMPL;
82
83    static {
84        if (Build.VERSION.SDK_INT >= 16) {
85            IMPL = new JellyBeanConnectivityManagerCompatImpl();
86        } else if (Build.VERSION.SDK_INT >= 13) {
87            IMPL = new HoneycombMR2ConnectivityManagerCompatImpl();
88        } else if (Build.VERSION.SDK_INT >= 8) {
89            IMPL = new GingerbreadConnectivityManagerCompatImpl();
90        } else {
91            IMPL = new BaseConnectivityManagerCompatImpl();
92        }
93    }
94
95    /**
96     * Returns if the currently active data network is metered. A network is
97     * classified as metered when the user is sensitive to heavy data usage on
98     * that connection. You should check this before doing large data transfers,
99     * and warn the user or delay the operation until another network is
100     * available.
101     */
102    public static boolean isActiveNetworkMetered(ConnectivityManager cm) {
103        return IMPL.isActiveNetworkMetered(cm);
104    }
105
106    /**
107     * Return the {@link NetworkInfo} that caused the given
108     * {@link ConnectivityManager#CONNECTIVITY_ACTION} broadcast. This obtains
109     * the current state from {@link ConnectivityManager} instead of using the
110     * potentially-stale value from
111     * {@link ConnectivityManager#EXTRA_NETWORK_INFO}.
112     */
113    public static NetworkInfo getNetworkInfoFromBroadcast(ConnectivityManager cm, Intent intent) {
114        final NetworkInfo info = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
115        return cm.getNetworkInfo(info.getType());
116    }
117}
118