Java tutorial
//package com.java2s; public class Main { public static byte[] HexToBuf(String auth) { int Leth = auth.length() / 2; byte[] HexByte = new byte[Leth]; for (int a = 0; a < Leth; a++) { HexByte[a] = (byte) Integer.parseInt(auth.substring(a * 2, a * 2 + 2).toLowerCase(), 16); } return HexByte; } }