code: public boolean equivalentTo(I other) {
  
          if (this.getContext() == other) {
              return true;
          }
  
          T startA = this.getClosedFiniteStart();
          T startB = other.getClosedFiniteStart();
  
          if (startA == null) {
              if (startB != null) {
                  return false;
              }
          } else if (startB == null) {
              return false;
          } else if (!startA.isSimultaneous(startB)) {
              return false;
          }
  
          T endA = this.end.getTemporal();
          T endB = other.getEnd().getTemporal();
  
          if (endA == null) {
              return (endB == null);
          } else if (endB == null) {
              return false;
          }
  
          if (this.getFactory().isCalendrical()) {
              if (this.end.isOpen()) {
                  endA = this.getTimeLine().stepBackwards(endA);
              }
              if (other.getEnd().isOpen()) {
                  endB = this.getTimeLine().stepBackwards(endB);
              }
          } else {
              if (this.end.isClosed()) {
                  endA = this.getTimeLine().stepForward(endA);
              }
              if (other.getEnd().isClosed()) {
                  endB = this.getTimeLine().stepForward(endB);
              }
          }
  
          if (endA == null) {
              return (endB == null);
          } else if (endB == null) {
              return false;
          } else {
              return endA.isSimultaneous(endB);
          }
  
      }
docs: /*[deutsch]
  <p>ALLEN-Relation: Ist dieses Intervall gleich dem anderen Intervall
  unter Ber&uuml;cksichtigung des offen/geschlossen-Zustands der
  Intervallgrenzen? </p>
  
  <p>Relation diagram: </p>
  
  <p><img src="doc-files/equivalent.jpg" alt="equivalent"></p>
  
  @param   other   another interval whose relation to this interval
  is to be investigated
  @return  {@code true} if this interval is temporally equivalent to
  the other one else {@code false}
  @since   2.0