1 /*
2  * Copyright (C) 2015 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 package com.android.providers.contacts.util;
17 
18 import android.content.ContentValues;
19 import android.database.Cursor;
20 import android.database.sqlite.SQLiteDatabase;
21 
22 /**
23  * Utilities related to "database properties", which are similar to shard preferences, but
24  * are transaction-aware.
25  */
26 public class PropertyUtils {
PropertyUtils()27     private PropertyUtils() {
28     }
29 
30     public interface Tables {
31         String PROPERTIES = "properties";
32     }
33 
34     public interface PropertiesColumns {
35         String PROPERTY_KEY = "property_key";
36         String PROPERTY_VALUE = "property_value";
37     }
38 
39     /**
40      * Creates the properties table.
41      */
createPropertiesTable(SQLiteDatabase db)42     public static void createPropertiesTable(SQLiteDatabase db) {
43         db.execSQL("CREATE TABLE " + Tables.PROPERTIES + " (" +
44                 PropertiesColumns.PROPERTY_KEY + " TEXT PRIMARY KEY, " +
45                 PropertiesColumns.PROPERTY_VALUE + " TEXT " +
46                 ");");
47 
48     }
49 
50     /**
51      * Gets a property.
52      */
getProperty(SQLiteDatabase db, String key, String defaultValue)53     public static String getProperty(SQLiteDatabase db, String key, String defaultValue) {
54         final Cursor cursor = db.query(Tables.PROPERTIES,
55                 new String[] {PropertiesColumns.PROPERTY_VALUE},
56                 PropertiesColumns.PROPERTY_KEY + "=?",
57                 new String[] {key}, null, null, null);
58         String value = null;
59         try {
60             if (cursor.moveToFirst()) {
61                 value = cursor.getString(0);
62             }
63         } finally {
64             cursor.close();
65         }
66 
67         return value != null ? value : defaultValue;
68     }
69 
70     /**
71      * Sets a property.
72      */
setProperty(SQLiteDatabase db, String key, String value)73     public static void setProperty(SQLiteDatabase db, String key, String value) {
74         ContentValues values = new ContentValues();
75         values.put(PropertiesColumns.PROPERTY_KEY, key);
76         values.put(PropertiesColumns.PROPERTY_VALUE, value);
77         db.replace(Tables.PROPERTIES, null, values);
78     }
79 }
80