public StringBuffer getPatchHeader() {
public String getPatchHeader() {
    public StringBuffer getPatchHeader() {        StringBuffer patchstring = new StringBuffer("F0");        byte[] data = null;        try {            data = messages[0].getData();        } catch (NullPointerException ex) {            return null;        }        int end = Math.min(16, data.length);        for (int i = 1; i < end; i++) {            if ((int) (data[i] & 0xff) < 0x10)                patchstring.append("0");            patchstring.append(Integer.toHexString((int) (data[i] & 0xff)));        }        return patchstring;    }