public void removeVariableListInitializer(VariableListContextInitializerConfiguration config) {
   _var_lists.remove(config);
   if (_listeners != null)
     for (ContextInitializerChangeListener listener : _listeners)
       listener.variableListInitializerRemoved(config);
 }
 public void addVariableListInitializer(VariableListContextInitializerConfiguration config) {
   _var_lists.add(config);
   if (_listeners != null)
     for (ContextInitializerChangeListener listener : _listeners)
       listener.variableListInitializerAdded(config);
 }