question: if the key is a proper key , return it , otherwise , return null concode_field_sep List<LWComponent> components concode_elem_sep String NO_OLD_VALUE concode_elem_sep LWComponent component concode_elem_sep Object oldValue concode_elem_sep Object source concode_elem_sep Object key concode_field_sep String paramString concode_elem_sep boolean hasOldValue concode_elem_sep String getName concode_elem_sep boolean isModelSourced concode_elem_sep boolean isUndoable concode_elem_sep LWComponent onlyComponent concode_elem_sep Object getSource concode_elem_sep List<LWComponent> getComponents concode_elem_sep String toString concode_elem_sep Object getOldValue concode_elem_sep LWComponent getComponent concode_elem_sep Object getCode
target: LWComponent . Key function ( ) { if ( this . key instanceof LWComponent . Key ) return ( LWComponent . Key ) key ; else return null ; }