question: @ Override public boolean equals ( Object object ) { if ( this == object ) { return true ; } if ( object instanceof Set ) { Set < ? > s = ( Set < ? > ) object ; try { return size ( ) == s . size ( ) && containsAll ( s ) ; } catch ( NullPointerException ignored ) { return false ; } catch ( ClassCastException ignored ) { return false ; } } return false ; }
target:  Compares the specified object to this Set and returns true if they are equal. The object must be an instance of Set and contain the same objects.