Java - jtextArea para numeros help me

import java.awt.event.KeyEvent;

import java.awt.event.KeyListener;

import javax.swing.BorderFactory;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.JTextArea;

import javax.swing.SwingUtilities;

public class SoloNumeros extends JFrame{

	private JTextArea areaNumeros;

	public SoloNumeros() {

		areaNumeros = new JTextArea(10, 20);

		areaNumeros.addKeyListener(new AceptarSoloNumeros());

		JPanel pnPrincipal = new JPanel();

		pnPrincipal.add(areaNumeros);

		pnPrincipal.setBorder(BorderFactory.createEmptyBorder(25, 25, 25, 25));

		setContentPane(pnPrincipal);

		setTitle("Solo números");

		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		pack();

		setLocationRelativeTo(null);

		setVisible(true);

	}

	private class AceptarSoloNumeros implements KeyListener {

		@Override

		public void keyTyped(KeyEvent e) {

			//Recogemos caracter introducido

			char caracter = e.getKeyChar();

			//Comprobamos si es un número

			switch(caracter) {

			case '1':

			case '2':

			case '3':

			case '4':

			case '5':

			case '6':

			case '7':

			case '8':

			case '9':

			case '0':

				//Es número, lo aceptamos

				areaNumeros.append(Character.toString(caracter));

			default:

				//¡¡No es número!! Lo rechazamos

				e.consume();

			}

		}

		@Override

		public void keyPressed(KeyEvent e) {}

		@Override

		public void keyReleased(KeyEvent e) {}

	}

	public static void main(String[] args) {

		SwingUtilities.invokeLater(new Runnable() {

			@Override

			public void run() {

				new SoloNumeros();

			}

		});

	}

}