code: public DescribeInstancesResult withReservations(Reservation... reservations) {
          if (this.reservations == null) {
              setReservations(new com.amazonaws.internal.SdkInternalList<Reservation>(reservations.length));
          }
          for (Reservation ele : reservations) {
              this.reservations.add(ele);
          }
          return this;
      }
docs: <p>
  Information about the reservations.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setReservations(java.util.Collection)} or {@link #withReservations(java.util.Collection)} if you want to
  override the existing values.
  </p>
  
  @param reservations
  Information about the reservations.
  @return Returns a reference to this object so that method calls can be chained together.