question: public void makeImmutable ( ) { if ( mutable ) { if ( results != null ) { int length = results . size ( ) ; for ( int i = 0 ; i < length ; i ++ ) { Result result = ( Result ) results . get ( i ) ; result . makeImmutable ( ) ; } results = Collections . unmodifiableList ( results ) ; } mutable = false ; } }
target:  Makes the object immutable