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 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 package jdk.test.lib; 25 26 import java.math.BigInteger; 27 28 /** 29 * Utility class containing conversions between strings, arrays, and numeric 30 * values. 31 */ 32 33 public class Convert { 34 35 // Convert from a byte array to a hexadecimal representation as a string. 36 public static String byteArrayToHexString(byte[] arr) { 37 StringBuilder result = new StringBuilder(); 38 for (int i = 0; i < arr.length; ++i) { 39 byte curVal = arr[i]; 40 result.append(Character.forDigit(curVal >> 4 & 0xF, 16)); 41 result.append(Character.forDigit(curVal & 0xF, 16)); 42 } 43 return result.toString(); 44 } 45 46 // Expand a single byte to a byte array 47 public static byte[] byteToByteArray(byte v, int length) { 48 byte[] result = new byte[length]; 49 result[0] = v; 50 return result; 51 } 52 53 // Convert a hexadecimal string to a byte array 54 public static byte[] hexStringToByteArray(String str) { 55 byte[] result = new byte[str.length() / 2]; 56 for (int i = 0; i < result.length; i++) { 57 result[i] = (byte) Character.digit(str.charAt(2 * i), 16); 58 result[i] <<= 4; 59 result[i] += Character.digit(str.charAt(2 * i + 1), 16); 60 } 61 return result; 62 } 63 64 /* 65 * Convert a hexadecimal string to the corresponding little-ending number 66 * as a BigInteger. The clearHighBit argument determines whether the most 67 * significant bit of the highest byte should be set to 0 in the result. 68 */ 69 public static 70 BigInteger hexStringToBigInteger(boolean clearHighBit, String str) { 71 BigInteger result = BigInteger.ZERO; 72 for (int i = 0; i < str.length() / 2; i++) { 73 int curVal = Character.digit(str.charAt(2 * i), 16); 74 curVal <<= 4; 75 curVal += Character.digit(str.charAt(2 * i + 1), 16); 76 if (clearHighBit && i == str.length() / 2 - 1) { 77 curVal &= 0x7F; 78 } 79 result = result.add(BigInteger.valueOf(curVal).shiftLeft(8 * i)); 80 } 81 return result; 82 } 83 } 84 85