| static <E extends @Nullable java.lang.Object>Sets.SetView<E>
 | Sets. difference(java.util.Set<E> set1,
          java.util.Set<?> set2) | Returns an unmodifiable view of the difference of two sets. | 
| static <E extends @Nullable java.lang.Object>Sets.SetView<E>
 | Sets. intersection(java.util.Set<E> set1,
            java.util.Set<?> set2) | Returns an unmodifiable view of the intersection of two sets. | 
| static <E extends @Nullable java.lang.Object>Sets.SetView<E>
 | Sets. symmetricDifference(java.util.Set<? extends E> set1,
                   java.util.Set<? extends E> set2) | Returns an unmodifiable view of the symmetric difference of two sets. | 
| static <E extends @Nullable java.lang.Object>Sets.SetView<E>
 | Sets. union(java.util.Set<? extends E> set1,
     java.util.Set<? extends E> set2) | Returns an unmodifiable view of the union of two sets. |