RunTime to keep the Thread running until it is closed

Question

I wish to open a PDF file in Acrobat Reader from a JMenuItem in swing application. Until the PDF file is open, I want that particular JMenuItem to be inactive (setEnabled(false)). Once the PDF file is closed, that JMenuItem will become active again (setEnabled(true)).
I will find the answer if I can keep the "cmd.exe" running until servletjsp.pdf is closed in the following class. Please advise!
import java.io.*;
class Runner2{
public static void main(String args[]){
Runtime r = Runtime.getRuntime();
try {
r.exec("cmd.exe /c start servletjsp.pdf");
catch(IOException e) {
e.printStackTrace();
}

Answer 1

I wish to open a PDF file in Acrobat Reader from a
JMenuItem in swing application. Until the PDF file is
open, I want that particular JMenuItem to be inactive
(setEnabled(false)). Once the PDF file is closed, that
JMenuItem will become active again (setEnabled(true)).
I will find the answer if I can keep the "cmd.exe"
running until servletjsp.pdf is closed in the
following class. Please advise!
try this.
import java.io.*;
class Runner2{
public static void main(String args[]){
Runtime r = Runtime.getRuntime();
try {
Process process = r.exec("cmd.exe /c start servletjsp.pdf");
process.waitFor();
catch(IOException e) {
e.printStackTrace();
}