cdm/src/main/java/ucar/nc2/units/DateRange.java
public boolean intersects(Date start_want, Date end_want) {
    if (isEmpty) return false;

    if (getStart().after(end_want)) return false;
    if (getEnd().before(start_want)) return false;

    return true;
  }
public boolean intersects(Date start_want, Date end_want) {
    if (isEmpty) return false;

    if (getStart().after(end_want)) return false;
    if (getEnd().before(start_want)) return false;

    return true;
  }
Determine if the given range intersects this date range.

@param start_want range starts here
@param end_want   range ends here
@return true if ranges intersect