cdm/src/main/java/ucar/nc2/units/DateRange.java
public void extend(DateRange dr) {
    boolean localEmpty = isEmpty;
    if (localEmpty || dr.getStart().before(getStart()))
      setStart(dr.getStart());
    if (localEmpty || getEnd().before(dr.getEnd()))
      setEnd(dr.getEnd());
  }
public void extend(DateRange dr) {
    boolean localEmpty = isEmpty;
    if (localEmpty || dr.getStart().before(getStart()))
      setStart(dr.getStart());
    if (localEmpty || getEnd().before(dr.getEnd()))
      setEnd(dr.getEnd());
  }
Extend this date range by the given one.

@param dr given DateRange