@Override
    public String toString() {
      if (this.direction == Direction.CURRENT) {
        return "currentRow";
      }

      return String.format("%s %s", (amt == UNBOUNDED_AMOUNT ? "Unbounded" : amt), direction);
    }
Returns true for bounded non-current frames.
@return
ql/src/java/org/apache/hadoop/hive/ql/parse/WindowingSpec.java