/*
* Copied from the DnsJava project
*
* Copyright (c) 1998-2011, Brian Wellington.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package io.milton.dns.utils;
/**
* A routine to produce a nice looking hex dump
*
* @author Brian Wellington
*/
public class hexdump {
private static final char [] hex = "0123456789ABCDEF".toCharArray();
/**
* Dumps a byte array into hex format.
* @param description If not null, a description of the data.
* @param b The data to be printed.
* @param offset The start of the data in the array.
* @param length The length of the data in the array.
*/
public static String
dump(String description, byte [] b, int offset, int length) {
StringBuilder sb = new StringBuilder();
sb.append(length).append("b");
if (description != null)
sb.append(" (").append(description).append(")");
sb.append(':');
int prefixlen = sb.toString().length();
prefixlen = (prefixlen + 8) & ~ 7;
sb.append('\t');
int perline = (80 - prefixlen) / 3;
for (int i = 0; i < length; i++) {
if (i != 0 && i % perline == 0) {
sb.append('\n');
for (int j = 0; j < prefixlen / 8 ; j++)
sb.append('\t');
}
int value = (int)(b[i + offset]) & 0xFF;
sb.append(hex[(value >> 4)]);
sb.append(hex[(value & 0xF)]);
sb.append(' ');
}
sb.append('\n');
return sb.toString();
}
public static String
dump(String s, byte [] b) {
return dump(s, b, 0, b.length);
}
}