Exit after initializing batch script from java-Collection of common programming errors

I want to initialize one batch script using java code. Once it is initialized I need to exit the java program and wants the batch script to continue executing. How can I achieve this. I used Runtime and Process to do this. But it is waiting for the batch script to finish before proceeding to the next. This is the sample program I tried out.

        try {
            Runtime r = Runtime.getRuntime();
            System.out.println("Executing process");
            Process p = r.exec("c:\\anoop\\ping.bat");
            System.out.println("Executed process"); 
            p.waitFor();
            System.out.println("Exiting with out :: ");
        } catch (Exception e) {// Catch exception if any
            System.err.println("Error: " + e.getMessage());
            e.printStackTrace();
        }

If I use p.exitValue(), it is giving error java.lang.IllegalThreadStateException: process has not exited. In short, I just want to initialize a batch script and then exit from the java program.

Thanks, Anoop