code: public DescribeHostReservationsRequest withHostReservationIdSet(String... hostReservationIdSet) {
          if (this.hostReservationIdSet == null) {
              setHostReservationIdSet(new com.amazonaws.internal.SdkInternalList<String>(hostReservationIdSet.length));
          }
          for (String ele : hostReservationIdSet) {
              this.hostReservationIdSet.add(ele);
          }
          return this;
      }
docs: <p>
  The host reservation IDs.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setHostReservationIdSet(java.util.Collection)} or {@link #withHostReservationIdSet(java.util.Collection)}
  if you want to override the existing values.
  </p>
  
  @param hostReservationIdSet
  The host reservation IDs.
  @return Returns a reference to this object so that method calls can be chained together.