/*
* Hex.java
*
* Created 04.07.2003.
*
* eaio: UUID - an implementation of the UUID specification Copyright (c) 2003-2009 Johann Burkard (jb@eaio.com)
* http://eaio.com.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
* documentation files (the "Software"), to deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
* WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
package com.eaio.util.lang;
import java.io.IOException;
/**
* Number-to-hexadecimal and hexadecimal-to-number conversions.
*
* @see <a href="http://johannburkard.de/software/uuid/">UUID</a>
* @author <a href="mailto:jb@eaio.com">Johann Burkard</a>
* @version $Id: Hex.java 1888 2009-03-15 12:43:24Z johann $
*/
public final class Hex {
/**
* No instances needed.
*/
private Hex() {
super();
}
private static final char[] DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e',
'f' };
/**
* Turns a <code>short</code> into hex octets.
*
* @param a the {@link Appendable}, may not be <code>null</code>
* @param in the integer
* @return {@link Appendable}
*/
public static Appendable append(Appendable a, short in) {
return append(a, (long) in, 4);
}
/**
* Turns a <code>short</code> into hex octets.
*
* @param a the {@link Appendable}, may not be <code>null</code>
* @param in the integer
* @param length the number of octets to produce
* @return {@link Appendable}
*/
public static Appendable append(Appendable a, short in, int length) {
return append(a, (long) in, length);
}
/**
* Turns an <code>int</code> into hex octets.
*
* @param a the {@link Appendable}, may not be <code>null</code>
* @param in the integer
* @return {@link Appendable}
*/
public static Appendable append(Appendable a, int in) {
return append(a, (long) in, 8);
}
/**
* Turns an <code>int</code> into hex octets.
*
* @param a the {@link Appendable}, may not be <code>null</code>
* @param in the integer
* @param length the number of octets to produce
* @return {@link Appendable}
*/
public static Appendable append(Appendable a, int in, int length) {
return append(a, (long) in, length);
}
/**
* Turns a <code>long</code> into hex octets.
*
* @param a the {@link Appendable}, may not be <code>null</code>
* @param in the long
* @return {@link Appendable}
*/
public static Appendable append(Appendable a, long in) {
return append(a, in, 16);
}
/**
* Turns a <code>long</code> into hex octets.
*
* @param a the {@link Appendable}, may not be <code>null</code>
* @param in the long
* @param length the number of octets to produce
* @return {@link Appendable}
*/
public static Appendable append(Appendable a, long in, int length) {
try {
int lim = (length << 2) - 4;
while (lim >= 0) {
a.append(DIGITS[(byte) (in >> lim) & 0x0f]);
lim -= 4;
}
}
catch (IOException ex) {
// Bla
}
return a;
}
/**
* Turns a <code>byte</code> array into hex octets.
*
* @param a the {@link Appendable}, may not be <code>null</code>
* @param bytes the <code>byte</code> array
* @return {@link Appendable}
*/
public static Appendable append(Appendable a, byte[] bytes) {
try {
for (byte b : bytes) {
a.append(DIGITS[(byte) ((b & 0xF0) >> 4)]);
a.append(DIGITS[(byte) (b & 0x0F)]);
}
}
catch (IOException ex) {
// Bla
}
return a;
}
/**
* Parses a <code>long</code> from a hex encoded number. This method will skip all characters that are not 0-9,
* A-F and a-f.
* <p>
* Returns 0 if the {@link CharSequence} does not contain any interesting characters.
*
* @param s the {@link CharSequence} to extract a <code>long</code> from, may not be <code>null</code>
* @return a <code>long</code>
* @throws NullPointerException if the {@link CharSequence} is <code>null</code>
*/
public static long parseLong(CharSequence s) {
long out = 0;
byte shifts = 0;
char c;
for (int i = 0; i < s.length() && shifts < 16; i++) {
c = s.charAt(i);
if ((c > 47) && (c < 58)) {
++shifts;
out <<= 4;
out |= c - 48;
}
else if ((c > 64) && (c < 71)) {
++shifts;
out <<= 4;
out |= c - 55;
}
else if ((c > 96) && (c < 103)) {
++shifts;
out <<= 4;
out |= c - 87;
}
}
return out;
}
/**
* Parses a <code>short</code> from a hex encoded number. This method will skip all characters that are not 0-9,
* A-F and a-f.
* <p>
* Returns 0 if the {@link CharSequence} does not contain any interesting characters.
*
* @param s the {@link CharSequence} to extract a <code>short</code> from, may not be <code>null</code>
* @return a <code>short</code>
* @throws NullPointerException if the {@link CharSequence} is <code>null</code>
*/
public static short parseShort(String s) {
short out = 0;
byte shifts = 0;
char c;
for (int i = 0; i < s.length() && shifts < 4; i++) {
c = s.charAt(i);
if ((c > 47) && (c < 58)) {
++shifts;
out <<= 4;
out |= c - 48;
}
else if ((c > 64) && (c < 71)) {
++shifts;
out <<= 4;
out |= c - 55;
}
else if ((c > 96) && (c < 103)) {
++shifts;
out <<= 4;
out |= c - 87;
}
}
return out;
}
}
