Java tutorial
//package com.java2s; /* * Copyright (C) 2009 Google Inc. All rights reserved. * * 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. */ import java.math.BigInteger; public class Main { /** * Converts an array of bytes to a string of hexadecimal characters. * Leading null bytes are preserved in the output. * <p> * The input byte stream is assumed to be a positive, two's complement * representation of an integer. The return value is the hexadecimal string * representation of this value. * * @param bytes the bytes to convert * @return the string representation */ public static String bytesToHexString(byte[] bytes) { if (bytes == null || bytes.length == 0) { return ""; } BigInteger bigint = new BigInteger(1, bytes); int formatLen = bytes.length * 2; return String.format("%0" + formatLen + "x", bigint); } }