1 /*
2  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
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7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24  */
25 
26 package sun.security.util;
27 
28 import java.util.List;
29 import java.util.function.BiFunction;
30 import java.security.*;
31 import jdk.internal.util.Preconditions;
32 
33 
34 /**
35  * This class holds the various utility methods for array range checks.
36  */
37 
38 public final class ArrayUtil {
39 
40     private static final BiFunction<String, List<Integer>,
41             ArrayIndexOutOfBoundsException> AIOOBE_SUPPLIER =
42             Preconditions.outOfBoundsExceptionFormatter
43             (ArrayIndexOutOfBoundsException::new);
44 
blockSizeCheck(int len, int blockSize)45     public static void blockSizeCheck(int len, int blockSize) {
46         if ((len % blockSize) != 0) {
47             throw new ProviderException("Internal error in input buffering");
48         }
49     }
50 
nullAndBoundsCheck(byte[] array, int offset, int len)51     public static void nullAndBoundsCheck(byte[] array, int offset, int len) {
52         // NPE is thrown when array is null
53         Preconditions.checkFromIndexSize(offset, len, array.length, AIOOBE_SUPPLIER);
54     }
55 
swap(byte[] arr, int i, int j)56     private static void swap(byte[] arr, int i, int j) {
57         byte tmp = arr[i];
58         arr[i] = arr[j];
59         arr[j] = tmp;
60     }
61 
reverse(byte [] arr)62     public static void reverse(byte [] arr) {
63         int i = 0;
64         int j = arr.length - 1;
65 
66         while (i < j) {
67             swap(arr, i, j);
68             i++;
69             j--;
70         }
71     }
72 }
73