/*
* Copyright (C)2009 - SSHJ Contributors
*
* 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.
*/
package net.schmizz.sshj.common;
/** Utility functions for byte arrays. */
public class ByteArrayUtils {
final static char[] digits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
/**
* Check whether some part or whole of two byte arrays is equal, for <code>length</code> bytes starting at some
* offset.
*
* @param a1
* @param a1Offset
* @param a2
* @param a2Offset
* @param length
*
* @return <code>true</code> or <code>false</code>
*/
public static boolean equals(byte[] a1, int a1Offset, byte[] a2, int a2Offset, int length) {
if (a1.length < a1Offset + length || a2.length < a2Offset + length)
return false;
while (length-- > 0)
if (a1[a1Offset++] != a2[a2Offset++])
return false;
return true;
}
/**
* Get a hexadecimal representation of a byte array starting at <code>offset</code> index for <code>len</code>
* bytes, with each octet separated by a space.
*
* @param array
* @param offset
* @param len
*
* @return hex string, each octet delimited by a space
*/
public static String printHex(byte[] array, int offset, int len) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < len; i++) {
byte b = array[offset + i];
if (sb.length() > 0)
sb.append(' ');
sb.append(digits[b >> 4 & 0x0F]);
sb.append(digits[b & 0x0F]);
}
return sb.toString();
}
/**
* Get the hexadecimal representation of a byte array.
*
* @param array
*
* @return hex string
*/
public static String toHex(byte[] array) {
return toHex(array, 0, array.length);
}
/**
* Get the hexadecimal representation of a byte array starting at <code>offset</code> index for <code>len</code>
* bytes.
*
* @param array
* @param offset
* @param len
*
* @return hex string
*/
public static String toHex(byte[] array, int offset, int len) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < len; i++) {
byte b = array[offset + i];
sb.append(digits[b >> 4 & 0x0F]);
sb.append(digits[b & 0x0F]);
}
return sb.toString();
}
}