Quest about a gui i'm trying to make that acts as a shell for jar command?

Question

I try to create a jar file from a whole directory and the program locks up. It only locks up if there is a another directory inside that directory that is being archived. I added a System.out.println(command) to see if the command being sent is the correct one, and it is.. so there is something going on with the run-time or an exception.. i ran some debugging tests and it seem as if the problem happens at this line of code:
                    child.waitFor();
but if i take that out.. i get another type of exception error which reads...
Exception occurred during event dispatching:
java.lang.IllegalThreadStateException: process has not exited
at java.lang.Win32Process.exitValue(Native Method)
at JarFrame.jarCreate(JarFrame.java:659)
at JarFrame.actionPerformed(JarFrame.java:330)
at java.awt.Button.processActionEvent(Button.java:329)
at java.awt.Button.processEvent(Button.java:302)
at java.awt.Component.dispatchEventImpl(Component.java:2595)
at java.awt.Component.dispatchEvent(Component.java:2499)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:319)
at java.awt.EventDispatchThread.pumpOneEvent(EventDispatchThread.java:10
3)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:84)
but the program doesn't lock up when this happens... but also at this point no directory at all can be archived... not even one without another directory inside it... the code for the create command is at the bottom... the code at the bottom archives a directory if the directory does not have another directory inside it.. but locks up when there is another directory inside the directory that is being archived... distinguishing if the file to archive is a directory or a file is not problem for the jarCreate() method.. it is at the exception waitfor() where the problem occurs...
PLEASE HELP!
thanks,
DiscoHristo
     /*     Runs the DOS Command for creating a JAR File     */
     public void jarCreate ( )
createFieldText = createField.getText();
String command;
String output = new String ("Jar File Created");
if (createFieldText.endsWith(".jar") == false)
     createFieldText = createFieldText.concat(".jar");
if (selectedDirectory == null)
     command = "jar cvfM " + createFieldText + " " + directoryOfFile + selectedFile;
               Runtime rt = Runtime.getRuntime();
               try
                    Process child = rt.exec(command);
                    child.waitFor();
                    textBox.append(output + '\n');
                    System.out.println("Process exit code is: " + child.exitValue());
               catch(IOException e)
                    System.err.println("IOException starting process!");
               catch(InterruptedException e)
                    System.err.println("Interrupted waiting for process!");
     if (selectedDirectory != null)
          command = "jar cvfM " + createFieldText + " " + selectedDirectory;
          System.out.println(command);
     Runtime rt = Runtime.getRuntime();
               try
                    Process child = rt.exec(command);
                    child.waitFor();
                    textBox.append(output + '\n');
                    System.out.println("Process exit code is: " + child.exitValue());
               catch(IOException e)
                    System.err.println("IOException starting process!");
               catch(InterruptedException e)
                    System.err.println("Interrupted waiting for process!");
     }

Answer 1

Hello,
Documentation says:
The Runtime.exec methods may not work well for special processes on certain native platforms, such as native windowing processes, daemon processes, Win16/DOS processes on Win32, or shell scripts.
Especially "may not work well" means that the behaviour of Runtime.exec is not documented in some "special" cases. Unfortunately I've same problem (unpredictable lock-ups) with Process.waitFor() in "standard environment" (Linux, J2SE 1.4, calling standard shell single processes). Could you be kind enough to let me know if you've found some solution?
Thanks,
Karel