adds the specified listener to the list of listeners . note that this method needs to be synchonized because it performs two independent operations on the underlying list concode_field_sep List<E> listeners concode_elem_sep long serialVersionUID concode_field_sep void writeExternal concode_elem_sep Iterator<E> getEventListenersIterator concode_elem_sep void removeEventListener concode_elem_sep void removeEventListener concode_elem_sep int size concode_elem_sep List<E> getEventListeners concode_elem_sep void readExternal concode_elem_sep boolean isEmpty concode_elem_sep void clear
void function ( final E arg0 ) { if ( ! this . listeners . contains ( arg0 ) ) { this . listeners . add ( arg0 ) ; } }