NetworkScoreManager.java revision 26fd143326a11c9dd7942e31acca6df56288d194 
1/*
2 * Copyright (C) 2014 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.net;
18
19import android.annotation.SdkConstant;
20import android.annotation.SdkConstant.SdkConstantType;
21import android.annotation.SystemApi;
22import android.content.Context;
23import android.content.Intent;
24import android.net.NetworkScorerAppManager.NetworkScorerAppData;
25import android.os.IBinder;
26import android.os.RemoteException;
27import android.os.ServiceManager;
28
29/**
30 * Class that manages communication between network subsystems and a network scorer.
31 *
32 * <p>You can get an instance of this class by calling
33 * {@link android.content.Context#getSystemService(String)}:
34 *
35 * <pre>NetworkScoreManager manager =
36 *     (NetworkScoreManager) getSystemService(Context.NETWORK_SCORE_SERVICE)</pre>
37 *
38 * <p>A network scorer is any application which:
39 * <ul>
40 * <li>Declares the {@link android.Manifest.permission#SCORE_NETWORKS} permission.
41 * <li>Includes a receiver for {@link #ACTION_SCORE_NETWORKS} guarded by the
42 *     {@link android.Manifest.permission#BROADCAST_SCORE_NETWORKS} permission which scores networks
43 *     and (eventually) calls {@link #updateScores} with the results. If this receiver specifies an
44 *     android:label attribute, this label will be used when referring to the application throughout
45 *     system settings; otherwise, the application label will be used.
46 * </ul>
47 *
48 * <p>The system keeps track of an active scorer application; at any time, only this application
49 * will receive {@link #ACTION_SCORE_NETWORKS} broadcasts and will be permitted to call
50 * {@link #updateScores}. Applications may determine the current active scorer with
51 * {@link #getActiveScorerPackage()} and request to change the active scorer by sending an
52 * {@link #ACTION_CHANGE_ACTIVE} broadcast with another scorer.
53 *
54 * @hide
55 */
56@SystemApi
57public class NetworkScoreManager {
58    /**
59     * Activity action: ask the user to change the active network scorer. This will show a dialog
60     * that asks the user whether they want to replace the current active scorer with the one
61     * specified in {@link #EXTRA_PACKAGE_NAME}. The activity will finish with RESULT_OK if the
62     * active scorer was changed or RESULT_CANCELED if it failed for any reason.
63     */
64    @SdkConstant(SdkConstantType.ACTIVITY_INTENT_ACTION)
65    public static final String ACTION_CHANGE_ACTIVE = "android.net.scoring.CHANGE_ACTIVE";
66
67    /**
68     * Extra used with {@link #ACTION_CHANGE_ACTIVE} to specify the new scorer package. Set with
69     * {@link android.content.Intent#putExtra(String, String)}.
70     */
71    public static final String EXTRA_PACKAGE_NAME = "packageName";
72
73    /**
74     * Broadcast action: new network scores are being requested. This intent will only be delivered
75     * to the current active scorer app. That app is responsible for scoring the networks and
76     * calling {@link #updateScores} when complete. The networks to score are specified in
77     * {@link #EXTRA_NETWORKS_TO_SCORE}, and will generally consist of all networks which have been
78     * configured by the user as well as any open networks.
79     *
80     * <p class="note">This is a protected intent that can only be sent by the system.
81     */
82    @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
83    public static final String ACTION_SCORE_NETWORKS = "android.net.scoring.SCORE_NETWORKS";
84
85    /**
86     * Extra used with {@link #ACTION_SCORE_NETWORKS} to specify the networks to be scored, as an
87     * array of {@link NetworkKey}s. Can be obtained with
88     * {@link android.content.Intent#getParcelableArrayExtra(String)}}.
89     */
90    public static final String EXTRA_NETWORKS_TO_SCORE = "networksToScore";
91
92    /**
93     * Activity action: launch a custom activity for configuring a scorer before enabling it.
94     * Scorer applications may choose to specify an activity for this action, in which case the
95     * framework will launch that activity which should return RESULT_OK if scoring was enabled.
96     *
97     * <p>If no activity is included in a scorer which implements this action, the system dialog for
98     * selecting a scorer will be shown instead.
99     */
100    @SdkConstant(SdkConstantType.ACTIVITY_INTENT_ACTION)
101    public static final String ACTION_CUSTOM_ENABLE = "android.net.scoring.CUSTOM_ENABLE";
102
103    /**
104     * Broadcast action: the active scorer has been changed. Scorer apps may listen to this to
105     * perform initialization once selected as the active scorer, or clean up unneeded resources
106     * if another scorer has been selected. Note that it is unnecessary to clear existing scores as
107     * this is handled by the system.
108     *
109     * <p>The new scorer will be specified in {@link #EXTRA_NEW_SCORER}.
110     *
111     * <p class="note">This is a protected intent that can only be sent by the system.
112     */
113    @SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION)
114    public static final String ACTION_SCORER_CHANGED = "android.net.scoring.SCORER_CHANGED";
115
116    /**
117     * Extra used with {@link #ACTION_SCORER_CHANGED} to specify the newly selected scorer's package
118     * name. Will be null if scoring was disabled. Can be obtained with
119     * {@link android.content.Intent#getStringExtra(String)}.
120     */
121    public static final String EXTRA_NEW_SCORER = "newScorer";
122
123    private final Context mContext;
124    private final INetworkScoreService mService;
125
126    /** @hide */
127    public NetworkScoreManager(Context context) {
128        mContext = context;
129        IBinder iBinder = ServiceManager.getService(Context.NETWORK_SCORE_SERVICE);
130        mService = INetworkScoreService.Stub.asInterface(iBinder);
131    }
132
133    /**
134     * Obtain the package name of the current active network scorer.
135     *
136     * <p>At any time, only one scorer application will receive {@link #ACTION_SCORE_NETWORKS}
137     * broadcasts and be allowed to call {@link #updateScores}. Applications may use this method to
138     * determine the current scorer and offer the user the ability to select a different scorer via
139     * the {@link #ACTION_CHANGE_ACTIVE} intent.
140     * @return the full package name of the current active scorer, or null if there is no active
141     *         scorer.
142     */
143    public String getActiveScorerPackage() {
144        NetworkScorerAppData app = NetworkScorerAppManager.getActiveScorer(mContext);
145        if (app == null) {
146            return null;
147        }
148        return app.mPackageName;
149    }
150
151    /**
152     * Update network scores.
153     *
154     * <p>This may be called at any time to re-score active networks. Scores will generally be
155     * updated quickly, but if this method is called too frequently, the scores may be held and
156     * applied at a later time.
157     *
158     * @param networks the networks which have been scored by the scorer.
159     * @return whether the update was successful.
160     * @throws SecurityException if the caller is not the active scorer.
161     */
162    public boolean updateScores(ScoredNetwork[] networks) throws SecurityException {
163        try {
164            return mService.updateScores(networks);
165        } catch (RemoteException e) {
166            return false;
167        }
168    }
169
170    /**
171     * Clear network scores.
172     *
173     * <p>Should be called when all scores need to be invalidated, i.e. because the scoring
174     * algorithm has changed and old scores can no longer be compared to future scores.
175     *
176     * <p>Note that scores will be cleared automatically when the active scorer changes, as scores
177     * from one scorer cannot be compared to those from another scorer.
178     *
179     * @return whether the clear was successful.
180     * @throws SecurityException if the caller is not the active scorer or privileged.
181     */
182    public boolean clearScores() throws SecurityException {
183        try {
184            return mService.clearScores();
185        } catch (RemoteException e) {
186            return false;
187        }
188    }
189
190    /**
191     * Set the active scorer to a new package and clear existing scores.
192     *
193     * @return true if the operation succeeded, or false if the new package is not a valid scorer.
194     * @throws SecurityException if the caller does not hold the
195     *         {@link android.Manifest.permission#BROADCAST_SCORE_NETWORKS} permission indicating
196     *         that it can manage scorer applications.
197     * @hide
198     */
199    public boolean setActiveScorer(String packageName) throws SecurityException {
200        try {
201            return mService.setActiveScorer(packageName);
202        } catch (RemoteException e) {
203            return false;
204        }
205    }
206
207    /**
208     * Turn off network scoring.
209     *
210     * <p>May only be called by the current scorer app, or the system.
211     *
212     * @throws SecurityException if the caller is neither the active scorer nor the system.
213     */
214    public void disableScoring() throws SecurityException {
215        try {
216            mService.disableScoring();
217        } catch (RemoteException e) {
218        }
219    }
220
221    /**
222     * Request scoring for networks.
223     *
224     * <p>Note that this is just a helper method to assemble the broadcast, and will run in the
225     * calling process.
226     *
227     * @return true if the broadcast was sent, or false if there is no active scorer.
228     * @throws SecurityException if the caller does not hold the
229     *         {@link android.Manifest.permission#BROADCAST_SCORE_NETWORKS} permission.
230     * @hide
231     */
232    public boolean requestScores(NetworkKey[] networks) throws SecurityException {
233        String activeScorer = getActiveScorerPackage();
234        if (activeScorer == null) {
235            return false;
236        }
237        Intent intent = new Intent(ACTION_SCORE_NETWORKS);
238        intent.setPackage(activeScorer);
239        intent.putExtra(EXTRA_NETWORKS_TO_SCORE, networks);
240        mContext.sendBroadcast(intent);
241        return true;
242    }
243
244    /**
245     * Register a network score cache.
246     *
247     * @param networkType the type of network this cache can handle. See {@link NetworkKey#type}.
248     * @param scoreCache implementation of {@link INetworkScoreCache} to store the scores.
249     * @throws SecurityException if the caller does not hold the
250     *         {@link android.Manifest.permission#BROADCAST_SCORE_NETWORKS} permission.
251     * @throws IllegalArgumentException if a score cache is already registered for this type.
252     * @hide
253     */
254    public void registerNetworkScoreCache(int networkType, INetworkScoreCache scoreCache) {
255        try {
256            mService.registerNetworkScoreCache(networkType, scoreCache);
257        } catch (RemoteException e) {
258        }
259    }
260}
261