Java tutorial
//package com.java2s; public class Main { public static String byteArr2HexStr(byte[] arrB) throws Exception { int iLen = arrB.length; StringBuffer sb = new StringBuffer(iLen * 2); for (int i = 0; i < iLen; ++i) { int intTmp; for (intTmp = arrB[i]; intTmp < 0; intTmp += 256) { ; } if (intTmp < 16) { sb.append("0"); } sb.append(Integer.toString(intTmp, 16).toUpperCase()); } return sb.toString(); } }