Detecting process exit in Java | adrian's blog

It would be very nice if the Process class would implement the Observable design pattern in some way. But it doesn’t and on this we will base our workaround creation.
Process contains a useful method for us, waitFor, that pauses the current thread execution until the given subprocess is finished. So, we will create a thread that will be suspended until the given subprocess is finished. Then we will fire the listeners to notify that the process has finished its execution.

public void run() {

        try {

            // wait for the process to finish

            process.waitFor();

            // invokes the listeners

            for (ProcessListener listener : listeners) {

                listener.processFinished(process);

            }

        } catch (InterruptedException e) {

        }

    }

processExitDetector = new ProcessExitDetector(subprocess);

processExitDetector .addProcessListener(new ProcessListener() {

    public void processFinished(Process process) {

        System.out.println("The subprocess has finished.");

    }

});

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