code: @XmlElementDecl(namespace = "http://www.opengis.net/gml", name = "_Datum", substitutionHeadNamespace = "http://www.opengis.net/gml", substitutionHeadName = "Definition")
      public JAXBElement<AbstractDatumType> create_Datum(AbstractDatumType value) {
          return new JAXBElement<AbstractDatumType>(__Datum_QNAME, AbstractDatumType.class, null, value);
      }
docs: Create an instance of {@link JAXBElement }{@code <}{@link AbstractDatumType }{@code >}
  
  @param value
  Java instance representing xml element's value.
  @return
  the new instance of {@link JAXBElement }{@code <}{@link AbstractDatumType }{@code >}