Java - Ejecutar un programa en consola de Java desde un Botón con Jframe

package programasCMD;

import java.util.Scanner;

public class HolaMundo {

	public static void main(String[] args) {

		Scanner teclado = new Scanner(System.in);

		System.out.println("Hola Mundo");

		System.out.println("\n\t\tFIN DE PROGRAMA");

		System.out.println("Pulse ENTER para cerrar continuar...");

		teclado.nextLine();

		teclado.close();

	}

}

package programasCMD;

import java.util.Scanner;

public class Sumar {

	public static void main(String[] args) {

		Scanner teclado = new Scanner(System.in);

		System.out.println("\t\tSUMAR DOS NUMEROS");

		System.out.print("Primer numero: ");

		int num1 = Integer.parseInt(teclado.nextLine());

		System.out.print("Segundo numero: ");

		int num2 = Integer.parseInt(teclado.nextLine());

		System.out.println("\nLa suma es: " + (num1+num2));

		System.out.println("\n\t\tFIN DE PROGRAMA");

		System.out.println("Pulse ENTER para cerrar continuar...");

		teclado.nextLine();

		teclado.close();

	}

}

public class Lanzador extends JFrame {

	private JButton btProg1;

	private JButton btProg2;

	public Lanzador() {

		btProg1 = new JButton("Saludo");

		btProg1.addActionListener(new LanzarSaludo());

		btProg2 = new JButton("Sumar");

		btProg2.addActionListener(new LanzarSuma());

		JPanel pnMensaje = new JPanel();

		pnMensaje.add(new JLabel("Elija un programa"));

		pnMensaje.setBorder(BorderFactory.createCompoundBorder(

				BorderFactory.createEmptyBorder(20,30,20,30),

				BorderFactory.createRaisedSoftBevelBorder()));

		JPanel pnBotones = new JPanel();

		pnBotones.add(btProg1);

		pnBotones.add(btProg2);

		pnBotones.setBorder(BorderFactory.createCompoundBorder(

				BorderFactory.createEmptyBorder(20,30,20,30),

				BorderFactory.createLoweredSoftBevelBorder()));

		setLayout(new BoxLayout(getContentPane(), BoxLayout.Y_AXIS));

		add(pnMensaje);

		add(pnBotones);

		setTitle("Lanzador");

		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		pack();

		setLocationRelativeTo(null);

		setVisible(true);

	}

	private void ocultar() {

		setVisible(false);

	}

	private void mostrar() {

		setVisible(true);

	}

	private class LanzarSaludo implements ActionListener {

		@Override

		public void actionPerformed(ActionEvent e) {

			ocultar();

			ProcessBuilder pb = new ProcessBuilder();

			pb.command(Arrays.asList("cmd", "/C", "Start","java", "HolaMundo.java"))

			          .directory(new File("src/programasCMD"));

			try {

				Process proceso = pb.start();

				while(proceso.isAlive());

				mostrar();

			} catch (Exception e1) {

				e1.printStackTrace();

			}

		}

	}

	private class LanzarSuma implements ActionListener {

		@Override

		public void actionPerformed(ActionEvent e) {

			ocultar();

			ProcessBuilder pb = new ProcessBuilder();

			pb.command(Arrays.asList("cmd", "/C", "Start","java", "Sumar.java"))

			          .directory(new File("src/programasCMD"));

			try {

				Process proceso = pb.start();

				while(proceso.isAlive());

				mostrar();

			} catch (Exception e1) {

				e1.printStackTrace();

			}

		}

	}

	public static void main(String[] args) {

		SwingUtilities.invokeLater(new Runnable() {

			@Override

			public void run() {

				new Lanzador();

			}

		});

	}

}

try {

				Process proceso = pb.start();

				while(proceso.isAlive());

				mostrar();

public class TestExec extends JFrame implements ActionListener {

	/* */

	TestExec() {

		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		JButton b_exec = new JButton("Launch proc");

		add(b_exec);

		b_exec.addActionListener(this);

		pack();

	}

	/* */

	@Override

	public void actionPerformed(ActionEvent e) {

		this.setState(ICONIFIED);

		try {

			File sal = new File("/tmp/output");

			ProcessBuilder pb = new ProcessBuilder("find", "/usr/local", "-ls");

			pb.redirectErrorStream(true);

			pb.redirectOutput(Redirect.appendTo(sal));

			Process pf = pb.start();

			pf.waitFor();

			this.setState(NORMAL);

		} catch(IOException | InterruptedException ex) {

			Logger.getLogger(TestExec.class.getName()).log(Level.SEVERE, null, ex);

		}

	}

	/* */

	public static void main(String[] args) {

		new TestExec().setVisible(true);

	}

}