[commands] Restart of DelegateCommand

[tfleis]

A JavaFX Service can be restarted by calling Service.restart(). If there is a current running task it is cancelled. The behaviour of a DelegateCommand is different. When you execute the DelegateCommand twice it is only started once.

if (inBackground) {
  if (!super.isRunning()) {
    reset();
    start();
  }
} 

A DelegateCommand is a Service so we can call DelegateCommand.restart() directly. By doing that we don't gain the advantages of the Command class (e.g. testability).

My expectation is:

if (inBackground) {
  super.restart();
} 

[mainrs]

I understand your argumentation. I would expect the same behavior as you. Still, would like to here something from @lestard or @sialcasa concerning this.

[manuel-mauky]

Sorry, I hadn't had time to respond. I will look into this issue on monday.

[manuel-mauky]

I've created a test case that verifies that both service and delegate command have equal behaviour regarding restarting. It works with your suggested fix.

As far as I can see this should work but I'm not as experienced as alex when it comes to Services and Commands. @sialcasa can you please review this issue and the provided fix?