Mega Code Archive
Convert a base16 string into a byte array
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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
/**
* Base 16 encoder.
*
* @author Marc Prud'hommeaux
* @nojavadoc
*/
class Base16Encoder {
private final static char[] HEX = new char[]{
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
/**
* Convert bytes to a base16 string.
*/
public static String encode(byte[] byteArray) {
StringBuffer hexBuffer = new StringBuffer(byteArray.length * 2);
for (int i = 0; i < byteArray.length; i++)
for (int j = 1; j >= 0; j--)
hexBuffer.append(HEX[(byteArray[i] >> (j * 4)) & 0xF]);
return hexBuffer.toString();
}
/**
* Convert a base16 string into a byte array.
*/
public static byte[] decode(String s) {
int len = s.length();
byte[] r = new byte[len / 2];
for (int i = 0; i < r.length; i++) {
int digit1 = s.charAt(i * 2), digit2 = s.charAt(i * 2 + 1);
if (digit1 >= '0' && digit1 <= '9')
digit1 -= '0';
else if (digit1 >= 'A' && digit1 <= 'F')
digit1 -= 'A' - 10;
if (digit2 >= '0' && digit2 <= '9')
digit2 -= '0';
else if (digit2 >= 'A' && digit2 <= 'F')
digit2 -= 'A' - 10;
r[i] = (byte) ((digit1 << 4) + digit2);
}
return r;
}
}
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