Here you can find the source of hexStringToBytes(String s)
public static byte[] hexStringToBytes(String s)
//package com.java2s; //License from project: Apache License public class Main { public static byte[] hexStringToBytes(String s) { int len = s.length(); byte[] data = new byte[len / 2]; for (int i = 0; i < len; i += 2) { data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4) + Character .digit(s.charAt(i + 1), 16)); }//from w ww .j a va2s.c o m return data; } }