/** Set the value on the underlying POJO, unwrapping values as necessary. */
  public void setDeclaredProperty(int propertyIndex, Object value) {
    SDOProperty declaredProperty =
        (SDOProperty) dataObject.getType().getDeclaredProperties().get(propertyIndex);
    if (declaredProperty.getType().isChangeSummaryType()) {
      return;
    }

    Mapping mapping = this.getJAXBMappingForProperty(declaredProperty);

    Object newValue = value;
    Object oldValue = mapping.getAttributeAccessor().getAttributeValueFromObject(entity);

    if (declaredProperty.getType().isDataType()) {
      if (!declaredProperty.isMany()) {
        AbstractSession session =
            ((JAXBContext) jaxbHelperContext.getJAXBContext()).getXMLContext().getSession(entity);
        XMLDirectMapping directMapping = (XMLDirectMapping) mapping;
        if (directMapping.hasConverter()) {
          newValue = directMapping.getConverter().convertDataValueToObjectValue(newValue, session);
        } else {
          CoreField field = mapping.getField();
          newValue =
              session
                  .getDatasourcePlatform()
                  .getConversionManager()
                  .convertObject(
                      newValue,
                      descriptor.getObjectBuilder().getFieldClassification((XMLField) field));
        }
      }
      mapping.setAttributeValueInObject(entity, newValue);
    } else if (declaredProperty.isMany()) {
      // Get a ListWrapper and set it's current elements
      ListWrapper listWrapper = (ListWrapper) getDeclaredProperty(propertyIndex);
      listWrapper.addAll((List) newValue);
    } else {
      // OLD VALUE
      if (mapping.isAbstractCompositeObjectMapping()) {
        XMLCompositeObjectMapping compositeMapping = (XMLCompositeObjectMapping) mapping;
        if (oldValue != null && compositeMapping.getContainerAccessor() != null) {
          compositeMapping.getContainerAccessor().setAttributeValueInObject(oldValue, null);
        }
      }

      // NEW VALUE
      newValue = jaxbHelperContext.unwrap((DataObject) value);
      mapping.getAttributeAccessor().setAttributeValueInObject(entity, newValue);
      if (mapping.isAbstractCompositeObjectMapping()) {
        XMLCompositeObjectMapping compositeMapping = (XMLCompositeObjectMapping) mapping;
        if (value != null && compositeMapping.getContainerAccessor() != null) {
          compositeMapping.getContainerAccessor().setAttributeValueInObject(newValue, entity);
        }
      }
    }
  }
  /**
   * For isMany=false properties set the value to null. For isMany=true set the value to an empty
   * container of the appropriate type.
   */
  public void unsetDeclaredProperty(int propertyIndex) {
    SDOProperty declaredProperty =
        (SDOProperty) dataObject.getType().getDeclaredProperties().get(propertyIndex);
    Mapping mapping = this.getJAXBMappingForProperty(declaredProperty);
    if (declaredProperty.isMany()) {
      ContainerMapping containerMapping = (ContainerMapping) mapping;
      ContainerPolicy containerPolicy = containerMapping.getContainerPolicy();

      // OLD VALUE
      if (mapping.isAbstractCompositeCollectionMapping()) {
        XMLCompositeCollectionMapping compositeMapping = (XMLCompositeCollectionMapping) mapping;
        if (compositeMapping.getContainerAccessor() != null) {

          Object oldContainer = mapping.getAttributeValueFromObject(entity);
          if (oldContainer != null) {
            AbstractSession session =
                ((JAXBContext) jaxbHelperContext.getJAXBContext())
                    .getXMLContext()
                    .getSession(entity);
            Object iterator = containerPolicy.iteratorFor(oldContainer);
            while (containerPolicy.hasNext(iterator)) {
              Object oldValue = containerPolicy.next(iterator, session);
              compositeMapping.getContainerAccessor().setAttributeValueInObject(oldValue, null);
            }
          }
        }
      }

      // NEW VALUE
      Object container = containerPolicy.containerInstance();
      mapping.getAttributeAccessor().setAttributeValueInObject(entity, container);
    } else {
      // OLD VALUE
      Object oldValue = mapping.getAttributeAccessor().getAttributeValueFromObject(entity);
      if (mapping.isAbstractCompositeObjectMapping()) {
        XMLCompositeObjectMapping compositeMapping = (XMLCompositeObjectMapping) mapping;
        if (compositeMapping.getContainerAccessor() != null) {
          if (oldValue != null) {
            compositeMapping.getContainerAccessor().setAttributeValueInObject(oldValue, null);
          }
        }
      }

      // NEW VALUE
      mapping.getAttributeAccessor().setAttributeValueInObject(entity, null);
    }
  }