code: public static Class<? extends AbstractElement<?, ?>> toElementClass(SegmentType elementType) {
          switch (elementType) {
              case t:
                  return Tenant.class;
              case e:
                  return Environment.class;
              case f:
                  return Feed.class;
              case m:
                  return Metric.class;
              case mt:
                  return MetricType.class;
              case r:
                  return Resource.class;
              case rt:
                  return ResourceType.class;
               case rl:
                  return Relationship.class;
              case d:
                  return DataEntity.class;
              case ot:
                  return OperationType.class;
              case mp:
                  return MetadataPack.class;
              default:
                  throw new IllegalStateException("There is no " + Entity.class.getName() + " type for " +
                          elementType.getClass().getName() + " '" + elementType.name() + "'");
          }
      }
docs: This should be used only in extreme cases where {@link SegmentType} is not possible.
  @param elementType the type of the element
  @return the class representing the element type