please include function rsyntaxTextArea_fixNumPad. sclass NumPadFixingInputMap extends InputMap { public void put(KeyStroke keyStroke, Object actionMapKey) { super.put(keyStroke, actionMapKey); Int code = rsyntaxTextArea_fixNumPad_map.get(keyStroke.getKeyCode()); if (code != null) put(KeyStroke.getKeyStroke(code, keyStroke.getModifiers()), actionMapKey); } void replaceOn(JComponent c) { InputMap im = c.getInputMap(); setParent(im.getParent()); for (KeyStroke key : im.keys()) put(key, im.get(key)); c.setInputMap(JComponent.WHEN_FOCUSED, this); } }