@Override
  public void setElementType(ObjectType elementType) {
    if (elementType instanceof StructType) {
      throw new IllegalArgumentException(
          "This collection does not support struct elements");
    }
    this.elementType = elementType;
  }
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