/** Performs the edit VM action when the Edit... button is pressed */
 private void editVM() {
   IStructuredSelection selection = (IStructuredSelection) fVMList.getSelection();
   VMStandin vm = (VMStandin) selection.getFirstElement();
   if (vm == null) {
     return;
   }
   if (JavaRuntime.isContributedVMInstall(vm.getId())) {
     VMDetailsDialog dialog = new VMDetailsDialog(getShell(), vm);
     dialog.open();
   } else {
     EditVMInstallWizard wizard =
         new EditVMInstallWizard(vm, fVMs.toArray(new IVMInstall[fVMs.size()]));
     WizardDialog dialog = new WizardDialog(getShell(), wizard);
     if (dialog.open() == Window.OK) {
       VMStandin result = wizard.getResult();
       if (result != null) {
         // replace with the edited VM
         int index = fVMs.indexOf(vm);
         fVMs.remove(index);
         fVMs.add(index, result);
         fVMList.setSelection(new StructuredSelection(result));
         fVMList.refresh(true);
       }
     }
   }
 }