1 /*
<lambda>null2 * Copyright (C) 2016 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
17 @file:JvmName("StringUtil")
18 @file:RestrictTo(RestrictTo.Scope.LIBRARY_GROUP_PREFIX) // used in generated code
19
20 package androidx.room.util
21
22 import androidx.annotation.RestrictTo
23 import kotlin.jvm.JvmField
24 import kotlin.jvm.JvmName
25
26 @Suppress("unused")
27 @JvmField
28 @Deprecated("No longer used by generated code")
29 val EMPTY_STRING_ARRAY = arrayOfNulls<String>(0)
30
31 /**
32 * Returns a new StringBuilder to be used while producing SQL queries.
33 *
34 * @return A new or recycled StringBuilder
35 */
36 @Deprecated("No longer used by generated code")
37 fun newStringBuilder(): StringBuilder = StringBuilder()
38
39 /**
40 * Adds bind variable placeholders (?) to the given string. Each placeholder is separated by a
41 * comma.
42 *
43 * @param builder The StringBuilder for the query
44 * @param count Number of placeholders
45 */
46 fun appendPlaceholders(builder: StringBuilder, count: Int) {
47 for (i in 0 until count) {
48 builder.append("?")
49 if (i < count - 1) {
50 builder.append(",")
51 }
52 }
53 }
54
55 /**
56 * Splits a comma separated list of integers to integer list.
57 *
58 * If an input is malformed, it is omitted from the result.
59 *
60 * @param input Comma separated list of integers.
61 * @return A List containing the integers or null if the input is null.
62 */
splitToIntListnull63 fun splitToIntList(input: String?): List<Int>? {
64 return input?.split(',')?.mapNotNull { item ->
65 try {
66 item.toInt()
67 } catch (ex: NumberFormatException) {
68 null
69 }
70 }
71 }
72
73 /**
74 * Joins the given list of integers into a comma separated list.
75 *
76 * @param input The list of integers.
77 * @return Comma separated string composed of integers in the list. If the list is null, return
78 * value is null.
79 */
joinIntoStringnull80 fun joinIntoString(input: List<Int>?): String? {
81 return input?.joinToString(",")
82 }
83