/*
* (C) 2007-2012 Alibaba Group Holding Limited.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* Authors:
* wuhua <wq163@163.com> , boyan <killme2008@gmail.com>
*/
package com.taobao.metamorphosis.utils;
/**
* Used to convert to hex from byte arrays and back.
*
* @version $Revision: 1.2 $
*/
public final class HexSupport {
private static final String[] HEX_TABLE = new String[] { "00", "01", "02", "03", "04", "05", "06", "07", "08",
"09", "0a", "0b", "0c", "0d", "0e", "0f", "10", "11", "12",
"13", "14", "15", "16", "17", "18", "19", "1a", "1b", "1c",
"1d", "1e", "1f", "20", "21", "22", "23", "24", "25", "26",
"27", "28", "29", "2a", "2b", "2c", "2d", "2e", "2f", "30",
"31", "32", "33", "34", "35", "36", "37", "38", "39", "3a",
"3b", "3c", "3d", "3e", "3f", "40", "41", "42", "43", "44",
"45", "46", "47", "48", "49", "4a", "4b", "4c", "4d", "4e",
"4f", "50", "51", "52", "53", "54", "55", "56", "57", "58",
"59", "5a", "5b", "5c", "5d", "5e", "5f", "60", "61", "62",
"63", "64", "65", "66", "67", "68", "69", "6a", "6b", "6c",
"6d", "6e", "6f", "70", "71", "72", "73", "74", "75", "76",
"77", "78", "79", "7a", "7b", "7c", "7d", "7e", "7f", "80",
"81", "82", "83", "84", "85", "86", "87", "88", "89", "8a",
"8b", "8c", "8d", "8e", "8f", "90", "91", "92", "93", "94",
"95", "96", "97", "98", "99", "9a", "9b", "9c", "9d", "9e",
"9f", "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7", "a8",
"a9", "aa", "ab", "ac", "ad", "ae", "af", "b0", "b1", "b2",
"b3", "b4", "b5", "b6", "b7", "b8", "b9", "ba", "bb", "bc",
"bd", "be", "bf", "c0", "c1", "c2", "c3", "c4", "c5", "c6",
"c7", "c8", "c9", "ca", "cb", "cc", "cd", "ce", "cf", "d0",
"d1", "d2", "d3", "d4", "d5", "d6", "d7", "d8", "d9", "da",
"db", "dc", "dd", "de", "df", "e0", "e1", "e2", "e3", "e4",
"e5", "e6", "e7", "e8", "e9", "ea", "eb", "ec", "ed", "ee",
"ef", "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", "f8",
"f9", "fa", "fb", "fc", "fd", "fe", "ff", };
private static final int[] INT_OFFSETS = new int[] { 24, 16, 8, 0 };
private HexSupport() {
}
/**
* @param hex
* @return
*/
public static byte[] toBytesFromHex(final String hex) {
final byte rc[] = new byte[hex.length() / 2];
for (int i = 0; i < rc.length; i++) {
final String h = hex.substring(i * 2, i * 2 + 2);
final int x = Integer.parseInt(h, 16);
rc[i] = (byte) x;
}
return rc;
}
/**
* @param bytes
* @return
*/
public static String toHexFromBytes(final byte[] bytes) {
final StringBuffer rc = new StringBuffer(bytes.length * 2);
for (int i = 0; i < bytes.length; i++) {
rc.append(HEX_TABLE[0xFF & bytes[i]]);
}
return rc.toString();
}
/**
*
* @param value
* @param trim
* if the leading 0's should be trimmed off.
* @return
*/
public static String toHexFromInt(final int value, boolean trim) {
final StringBuffer rc = new StringBuffer(INT_OFFSETS.length * 2);
for (int i = 0; i < INT_OFFSETS.length; i++) {
final int b = 0xFF & value >> INT_OFFSETS[i];
if (!(trim && b == 0)) {
rc.append(HEX_TABLE[b]);
trim = false;
}
}
return rc.toString();
}
}