Alex Klyubin | dcdaf87 | 2015-05-13 15:57:09 -0700 | [diff] [blame] | 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 | |
| 17 | package android.security.keystore; |
Alex Klyubin | 5927c9f | 2015-04-10 13:28:03 -0700 | [diff] [blame] | 18 | |
| 19 | import libcore.util.EmptyArray; |
| 20 | |
| 21 | /** |
| 22 | * @hide |
| 23 | */ |
Alex Klyubin | 3f8d4d8 | 2015-05-13 09:15:00 -0700 | [diff] [blame] | 24 | public abstract class ArrayUtils { |
Alex Klyubin | 5927c9f | 2015-04-10 13:28:03 -0700 | [diff] [blame] | 25 | private ArrayUtils() {} |
| 26 | |
| 27 | public static String[] nullToEmpty(String[] array) { |
| 28 | return (array != null) ? array : EmptyArray.STRING; |
| 29 | } |
| 30 | |
| 31 | public static String[] cloneIfNotEmpty(String[] array) { |
| 32 | return ((array != null) && (array.length > 0)) ? array.clone() : array; |
| 33 | } |
| 34 | |
Alex Klyubin | 7cbcfd4 | 2015-05-28 11:07:19 -0700 | [diff] [blame] | 35 | public static byte[] cloneIfNotEmpty(byte[] array) { |
| 36 | return ((array != null) && (array.length > 0)) ? array.clone() : array; |
| 37 | } |
| 38 | |
Alex Klyubin | 5927c9f | 2015-04-10 13:28:03 -0700 | [diff] [blame] | 39 | public static byte[] concat(byte[] arr1, byte[] arr2) { |
| 40 | return concat(arr1, 0, (arr1 != null) ? arr1.length : 0, |
| 41 | arr2, 0, (arr2 != null) ? arr2.length : 0); |
| 42 | } |
| 43 | |
| 44 | public static byte[] concat(byte[] arr1, int offset1, int len1, byte[] arr2, int offset2, |
| 45 | int len2) { |
| 46 | if (len1 == 0) { |
| 47 | return subarray(arr2, offset2, len2); |
| 48 | } else if (len2 == 0) { |
| 49 | return subarray(arr1, offset1, len1); |
| 50 | } else { |
| 51 | byte[] result = new byte[len1 + len2]; |
| 52 | System.arraycopy(arr1, offset1, result, 0, len1); |
| 53 | System.arraycopy(arr2, offset2, result, len1, len2); |
| 54 | return result; |
| 55 | } |
| 56 | } |
| 57 | |
Rob Barnes | 73ea619 | 2019-11-26 10:56:55 -0700 | [diff] [blame^] | 58 | /** |
| 59 | * Copies a subset of the source array to the destination array. |
| 60 | * Length will be limited to the bounds of source and destination arrays. |
| 61 | * The length actually copied is returned, which will be <= length argument. |
| 62 | * @param src is the source array |
| 63 | * @param srcOffset is the offset in the source array. |
| 64 | * @param dst is the destination array. |
| 65 | * @param dstOffset is the offset in the destination array. |
| 66 | * @param length is the length to be copied from source to destination array. |
| 67 | * @return The length actually copied from source array. |
| 68 | */ |
| 69 | public static int copy(byte[] src, int srcOffset, byte[] dst, int dstOffset, int length) { |
| 70 | if (dst == null || src == null) { |
| 71 | return 0; |
| 72 | } |
| 73 | if (length > dst.length - dstOffset) { |
| 74 | length = dst.length - dstOffset; |
| 75 | } |
| 76 | if (length > src.length - srcOffset) { |
| 77 | length = src.length - srcOffset; |
| 78 | } |
| 79 | if (length <= 0) { |
| 80 | return 0; |
| 81 | } |
| 82 | System.arraycopy(src, srcOffset, dst, dstOffset, length); |
| 83 | return length; |
| 84 | } |
| 85 | |
Alex Klyubin | 5927c9f | 2015-04-10 13:28:03 -0700 | [diff] [blame] | 86 | public static byte[] subarray(byte[] arr, int offset, int len) { |
| 87 | if (len == 0) { |
| 88 | return EmptyArray.BYTE; |
| 89 | } |
| 90 | if ((offset == 0) && (len == arr.length)) { |
| 91 | return arr; |
| 92 | } |
| 93 | byte[] result = new byte[len]; |
| 94 | System.arraycopy(arr, offset, result, 0, len); |
| 95 | return result; |
| 96 | } |
| 97 | |
| 98 | public static int[] concat(int[] arr1, int[] arr2) { |
| 99 | if ((arr1 == null) || (arr1.length == 0)) { |
| 100 | return arr2; |
| 101 | } else if ((arr2 == null) || (arr2.length == 0)) { |
| 102 | return arr1; |
| 103 | } else { |
| 104 | int[] result = new int[arr1.length + arr2.length]; |
| 105 | System.arraycopy(arr1, 0, result, 0, arr1.length); |
| 106 | System.arraycopy(arr2, 0, result, arr1.length, arr2.length); |
| 107 | return result; |
| 108 | } |
| 109 | } |
| 110 | } |