Here you can find the source of toHexString(byte[] b)
public static String toHexString(byte[] b)
//package com.java2s; /**//from w ww . ja va 2 s . c om * Copyright 2008 - 2009 * * 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. * * @project loonframework * @author chenpeng * @email?ceponline@yahoo.com.cn * @version 0.1 */ public class Main { private static final String[] hexDigits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" }; public static String toHexString(byte[] b) { StringBuffer resultSb = new StringBuffer(); for (int i = 0; i < b.length; i++) { resultSb.append(byteToHexString(b[i])); } return resultSb.toString(); } public static String toHexString(final int i) { StringBuffer buf = new StringBuffer(); appendHex(buf, i); return buf.toString(); } public static String byteToHexString(byte b) { int n = b; if (n < 0) n = 256 + n; int d1 = n / 16; int d2 = n % 16; return hexDigits[d1] + hexDigits[d2]; } public static void appendHex(final StringBuffer buf, final int i) { buf.append(Integer.toHexString((i >> 24) & 0xff)); buf.append(Integer.toHexString((i >> 16) & 0xff)); buf.append(Integer.toHexString((i >> 8) & 0xff)); buf.append(Integer.toHexString(i & 0xff)); } }