/**
 * Converts a string to the hex representations of its chars.
 */
Selection[] selection = textArea.getSelection();
String s = textArea.getSelectedText(selection[0]);
StringBuffer sb = new StringBuffer();
for (int i = 0; i < s.length(); i++) {
	String b = Integer.toHexString((int) s.charAt(i));
	for (int n = b.length(); n < 2; n++) {
		sb.append("0");
	}
	sb.append(b.toUpperCase());
}
textArea.setSelectedText(selection[0],sb.toString());