Java exec() child termination problem

Question

Hello,
I am trying to use exec() to launch a java application from a Java Swing GUI. The problem is that If any of the applications call System.exit() or Runtime.exit(), all applications will terminate. How do I prevent the GUI from closing when the child closes? I have attached the code I am using for reference.
Thanks in advance
  public void COmpileAndRun()
        String command = "javac Driver.java";
        try
            Runtime rt = Runtime.getRuntime(); //Process process = new ProcessBuilder(command).start();
            Process proc = rt.exec( command ); //Process process = new ProcessBuilder(command).start();
            InputStream stderr = proc.getErrorStream();
            InputStreamReader isr = new InputStreamReader(stderr);
            BufferedReader br = new BufferedReader(isr);
            String line = null;
            System.out.println("<ERROR>");
            while ( (line = br.readLine()) != null)
                System.out.println(line);
            System.out.println("</ERROR>");
            int exitVal = proc.waitFor();
            System.out.println("Process exitValue: " + exitVal);
            if( exitVal == 0 )
                command = "java Driver";
                proc = rt.exec( command );
                stderr = proc.getErrorStream();
                isr = new InputStreamReader(stderr);
                br = new BufferedReader(isr);
                line = null;
                System.out.println("<ERROR>");
                while ( (line = br.readLine()) != null)
                    System.out.println(line);
                System.out.println("</ERROR>");
                exitVal = proc.waitFor();
                System.out.println("Process exitValue: " + exitVal);
        } catch (Throwable t)
            t.printStackTrace();
}

Answer 1

String[] command =
   "java",
   "-cp",
   "my_class_path", // No extra quoting needed here
   "org.jetel.main.runGraph",
   "param1",
   "param2",
   "param3" // etc
Process process = Runtime.getRuntime().exec(command);