Here you can find the source of toHex(byte[] arr)
public static String toHex(byte[] arr)
//package com.java2s; /**// w w w .j av a 2 s . com Util.java Copyright (C) 1999, Claymore Systems, Inc. All Rights Reserved. ekr@rtfm.com Tue May 11 17:45:23 1999 This package is a SSLv3/TLS implementation written by Eric Rescorla <ekr@rtfm.com> and licensed by Claymore Systems, Inc. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. 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. 3. All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed by Claymore Systems, Inc. 4. Neither the name of Claymore Systems, Inc. nor the name of Eric Rescorla may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. $Id: Util.java,v 1.1.1.1 2003/05/09 20:36:14 gawor Exp $ */ public class Main { static String hex[] = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" }; public static String toHex(byte[] arr) { StringBuffer str = new StringBuffer(); for (int i = 0; i < arr.length; i++) { str.append(hex[(arr[i] >> 4) & 0x0f]); str.append(hex[arr[i] & 0x0f]); } return str.toString(); } }