code: public boolean hasBaseUnit(ChronoElement<?> element) {
  
          if (element == null) {
              return false;
          }
  
          boolean found = this.baseUnits.containsKey(element);
  
          if (
              !found
              && (element instanceof BasicElement)
          ) {
              ChronoElement<?> parent = ((BasicElement) element).getParent();
              found = ((parent != null) && this.baseUnits.containsKey(parent));
          }
  
          return found;
  
      }
docs: /*[deutsch]
  <p>Ermittelt, ob das angegebene Element eine Basiseinheit hat. </p>
  
  @param   element     chronological element (optional)
  @return  {@code true} if given element has a base unit else {@code false}
  @see     #getBaseUnit(ChronoElement)