public void reserve ( String name ) { checkName ( name ) ; // if this is new if ( reserved . add ( name ) ) { // add it to names, so that generateName will still work for reserved names (they will just // get suffixes). if ( ! names . add ( name ) ) { names . remove ( name ) ; throw new IllegalArgumentException ( "newly reserved name: " + name + " was already used!" ) ; } } }
Reserves the name useful for keywords .