question: public void deleteAll ( ) { Integer oldSize = Integer . valueOf ( _hashTable . size ( ) ) ; Enumeration < String > en = _hashTable . keys ( ) ; while ( en . hasMoreElements ( ) ) { RollingStock rs = getById ( en . nextElement ( ) ) ; rs . dispose ( ) ; _hashTable . remove ( rs . getId ( ) ) ; } firePropertyChange ( LISTLENGTH_CHANGED_PROPERTY , oldSize , Integer . valueOf ( _hashTable . size ( ) ) ) ; }
target:  Remove all RollingStock from roster