1/* 2 * Copyright (C) 2011 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.database; 18 19import android.text.TextUtils; 20 21/** 22 * Helper for accessing features in {@link android.database.DatabaseUtils} 23 * introduced after API level 4 in a backwards compatible fashion. 24 */ 25public class DatabaseUtilsCompat { 26 27 private DatabaseUtilsCompat() { 28 /* Hide constructor */ 29 } 30 31 /** 32 * Concatenates two SQL WHERE clauses, handling empty or null values. 33 */ 34 public static String concatenateWhere(String a, String b) { 35 if (TextUtils.isEmpty(a)) { 36 return b; 37 } 38 if (TextUtils.isEmpty(b)) { 39 return a; 40 } 41 42 return "(" + a + ") AND (" + b + ")"; 43 } 44 45 /** 46 * Appends one set of selection args to another. This is useful when adding a selection 47 * argument to a user provided set. 48 */ 49 public static String[] appendSelectionArgs(String[] originalValues, String[] newValues) { 50 if (originalValues == null || originalValues.length == 0) { 51 return newValues; 52 } 53 String[] result = new String[originalValues.length + newValues.length ]; 54 System.arraycopy(originalValues, 0, result, 0, originalValues.length); 55 System.arraycopy(newValues, 0, result, originalValues.length, newValues.length); 56 return result; 57 } 58} 59