public Collection<Set<Integer>> valueSets() {
        // An IntSet _is_ a Set<Integer>, but the JVM doesn't recognize
        // covaraince in the return type generics, so we must cast
        Collection<?> c = map.valueCollection();
        @SuppressWarnings("unchecked")
        Collection<Set<Integer>> c2 = (Collection<Set<Integer>>)c;            
        return c2;
    }
public Collection < Set < Integer > > valueSets ( ) { Collection < ? > c = map . valueCollection ( ) ; @ SuppressWarnings ( "unchecked" ) Collection < Set < Integer > > c2 = ( Collection < Set < Integer > > ) c ; return c2 ; }
{@inheritDoc}