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.provider;
18
19import android.annotation.SystemApi;
20import android.content.ContentProvider;
21import android.content.ContentValues;
22import android.content.Context;
23import android.content.UriMatcher;
24import android.content.pm.ProviderInfo;
25import android.database.Cursor;
26import android.net.Uri;
27
28/**
29 * Base class for a search indexable provider. Such provider offers data to be indexed either
30 * as a reference to an XML file (like a {@link android.preference.PreferenceScreen}) or either
31 * as some raw data.
32 *
33 * @see SearchIndexableResource
34 * @see SearchIndexableData
35 * @see SearchIndexablesContract
36 *
37 * To create a search indexables provider, extend this class, then implement the abstract methods,
38 * and add it to your manifest like this:
39 *
40 * <pre class="prettyprint">&lt;manifest&gt;
41 *    ...
42 *    &lt;application&gt;
43 *        ...
44 *        &lt;provider
45 *            android:name="com.example.MyIndexablesProvider"
46 *            android:authorities="com.example.myindexablesprovider"
47 *            android:exported="true"
48 *            android:grantUriPermissions="true"
49 *            android:permission="android.permission.READ_SEARCH_INDEXABLES"
50 *            &lt;intent-filter&gt;
51 *                &lt;action android:name="android.content.action.SEARCH_INDEXABLES_PROVIDER" /&gt;
52 *            &lt;/intent-filter&gt;
53 *        &lt;/provider&gt;
54 *        ...
55 *    &lt;/application&gt;
56 *&lt;/manifest&gt;</pre>
57 * <p>
58 * When defining your provider, you must protect it with
59 * {@link android.Manifest.permission#READ_SEARCH_INDEXABLES}, which is a permission only the system
60 * can obtain.
61 * </p>
62 *
63 * @hide
64 */
65@SystemApi
66public abstract class SearchIndexablesProvider extends ContentProvider {
67    private static final String TAG = "IndexablesProvider";
68
69    private String mAuthority;
70    private UriMatcher mMatcher;
71
72    private static final int MATCH_RES_CODE = 1;
73    private static final int MATCH_RAW_CODE = 2;
74    private static final int MATCH_NON_INDEXABLE_KEYS_CODE = 3;
75
76    /**
77     * Implementation is provided by the parent class.
78     */
79    @Override
80    public void attachInfo(Context context, ProviderInfo info) {
81        mAuthority = info.authority;
82
83        mMatcher = new UriMatcher(UriMatcher.NO_MATCH);
84        mMatcher.addURI(mAuthority, SearchIndexablesContract.INDEXABLES_XML_RES_PATH,
85                MATCH_RES_CODE);
86        mMatcher.addURI(mAuthority, SearchIndexablesContract.INDEXABLES_RAW_PATH,
87                MATCH_RAW_CODE);
88        mMatcher.addURI(mAuthority, SearchIndexablesContract.NON_INDEXABLES_KEYS_PATH,
89                MATCH_NON_INDEXABLE_KEYS_CODE);
90
91        // Sanity check our setup
92        if (!info.exported) {
93            throw new SecurityException("Provider must be exported");
94        }
95        if (!info.grantUriPermissions) {
96            throw new SecurityException("Provider must grantUriPermissions");
97        }
98        if (!android.Manifest.permission.READ_SEARCH_INDEXABLES.equals(info.readPermission)) {
99            throw new SecurityException("Provider must be protected by READ_SEARCH_INDEXABLES");
100        }
101
102        super.attachInfo(context, info);
103    }
104
105    @Override
106    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
107                        String sortOrder) {
108        switch (mMatcher.match(uri)) {
109            case MATCH_RES_CODE:
110                return queryXmlResources(null);
111            case MATCH_RAW_CODE:
112                return queryRawData(null);
113            case MATCH_NON_INDEXABLE_KEYS_CODE:
114                return queryNonIndexableKeys(null);
115            default:
116                throw new UnsupportedOperationException("Unknown Uri " + uri);
117        }
118    }
119
120    /**
121     * Returns all {@link android.provider.SearchIndexablesContract.XmlResource}.
122     *
123     * Those are Xml resource IDs to some {@link android.preference.PreferenceScreen}.
124     *
125     * @param projection list of {@link android.provider.SearchIndexablesContract.XmlResource}
126     *                   columns to put into the cursor. If {@code null} all supported columns
127     *                   should be included.
128     */
129    public abstract Cursor queryXmlResources(String[] projection);
130
131    /**
132     * Returns all {@link android.provider.SearchIndexablesContract.RawData}.
133     *
134     * Those are the raw indexable data.
135     *
136     * @param projection list of {@link android.provider.SearchIndexablesContract.RawData} columns
137     *                   to put into the cursor. If {@code null} all supported columns should be
138     *                   included.
139     */
140    public abstract Cursor queryRawData(String[] projection);
141
142    /**
143     * Returns all {@link android.provider.SearchIndexablesContract.NonIndexableKey}.
144     *
145     * Those are the non indexable data keys.
146     *
147     * @param projection list of {@link android.provider.SearchIndexablesContract.NonIndexableKey}
148     *                   columns to put into the cursor. If {@code null} all supported columns
149     *                   should be included.
150     */
151    public abstract Cursor queryNonIndexableKeys(String[] projection);
152
153    @Override
154    public String getType(Uri uri) {
155        switch (mMatcher.match(uri)) {
156            case MATCH_RES_CODE:
157                return SearchIndexablesContract.XmlResource.MIME_TYPE;
158            case MATCH_RAW_CODE:
159                return SearchIndexablesContract.RawData.MIME_TYPE;
160            case MATCH_NON_INDEXABLE_KEYS_CODE:
161                return SearchIndexablesContract.NonIndexableKey.MIME_TYPE;
162            default:
163                throw new IllegalArgumentException("Unknown URI " + uri);
164        }
165    }
166
167    /**
168     * Implementation is provided by the parent class. Throws by default, and cannot be overriden.
169     */
170    @Override
171    public final Uri insert(Uri uri, ContentValues values) {
172        throw new UnsupportedOperationException("Insert not supported");
173    }
174
175    /**
176     * Implementation is provided by the parent class. Throws by default, and cannot be overriden.
177     */
178    @Override
179    public final int delete(Uri uri, String selection, String[] selectionArgs) {
180        throw new UnsupportedOperationException("Delete not supported");
181    }
182
183    /**
184     * Implementation is provided by the parent class. Throws by default, and cannot be overriden.
185     */
186    @Override
187    public final int update(
188            Uri uri, ContentValues values, String selection, String[] selectionArgs) {
189        throw new UnsupportedOperationException("Update not supported");
190    }
191}
192