@Override
 public void canApply() throws ConfigurationException {
   super.canApply();
   if (myClasspathFormatPanel != null) {
     final String storageID = myClasspathFormatPanel.getSelectedClasspathFormat();
     ClasspathStorage.getProvider(storageID).assertCompatible(getModel());
   }
 }
 @Override
 public void apply() throws ConfigurationException {
   if (myClasspathFormatPanel != null) {
     myClasspathFormatPanel.apply();
   }
 }
 @Override
 public boolean isModified() {
   return super.isModified()
       || (myClasspathFormatPanel != null && myClasspathFormatPanel.isModified());
 }