@Override
  public Set asSet() {
    return this;
  }
Implementation of SelectResults that extends TreeSet This is the sorted version of ResultSet used
for order by clause If the elements are Structs, then use SortedStructSet instead.

@since GemFire 4.0
geode-core/src/main/java/org/apache/geode/cache/query/internal/SortedResultSet.java