Here you can find the source of bytesToHex(byte[] bytes)
public static String bytesToHex(byte[] bytes)
//package com.java2s; /**// ww w .j av a 2 s .co m * @license * Copyright 2016 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. */ public class Main { public static String bytesToHex(byte[] bytes) { // bytesToHex is used to convert output from Cipher. // cipher.update can return null, which is equivalent to returning // no plaitext rsp. ciphertext. if (bytes == null) { return ""; } String chars = "0123456789abcdef"; StringBuilder result = new StringBuilder(2 * bytes.length); for (byte b : bytes) { // convert to unsigned int val = b & 0xff; result.append(chars.charAt(val / 16)); result.append(chars.charAt(val % 16)); } return result.toString(); } }