How to add a timeout value when using Java's Runtime.exec()?

Question

I have a method I am using to execute a command on the local host. I\'d like to add a timeout parameter to the method so that if the command being called doesn\'t finish in

Answer 1

There are various ways to do this, but I'd consider using an Executor-- it just helps you encapsulate passing the exit value or exception from the thread back to the original caller.

    final Process p = ...        
    Callable call = new Callable() {
    public Integer call() throws Exception {
        p.waitFor();
        return p.exitValue();
      }
    };
    Future ft = Executors.newSingleThreadExecutor().submit(call);
    try {
      int exitVal = ft.get(2000L, TimeUnit.MILLISECONDS);
      return exitVal;
    } catch (TimeoutException to) {
      p.destroy();
      throw to;
    }

I think you can't get round the race condition whereby the wait times out, and then process terminates just before you call destroy().