public String byte2hex(byte[] b) { 
		String hs = ""; 
		String stmp = ""; 
		for (int i = 0; i < b.length; i++) { 
		stmp = Integer.toHexString(b[i] & 0xFF); 
		if (stmp.length() == 1) { 
		hs += "0" + stmp; 
		} 
		else { 
		hs += stmp; 
		} 
		} 
		return hs.toUpperCase(); 
		}