Here you can find the source of toHexString(byte[] bytes)
public static String toHexString(byte[] bytes)
//package com.java2s; //License from project: Apache License public class Main { private static final String STR_0 = "0"; public static String toHexString(byte[] bytes) { StringBuilder sb = new StringBuilder(bytes.length * 2); int i;// w w w . j a va 2s. c o m for (i = 0; i < bytes.length; i++) { if ((bytes[i] & 0xff) < 0x10) sb.append(STR_0); sb.append(Long.toString(bytes[i] & 0xff, 16)); } return sb.toString(); } }