private void drawFlowElements(
      Collection<FlowElement> elementList,
      Map<String, GraphicInfo> locationMap,
      ContainerShape parentShape,
      Process process) {

    final IFeatureProvider featureProvider = getDiagramTypeProvider().getFeatureProvider();

    List<FlowElement> noDIList = new ArrayList<FlowElement>();
    for (FlowElement flowElement : elementList) {

      if (flowElement instanceof SequenceFlow) {
        continue;
      }

      AddContext context = new AddContext(new AreaContext(), flowElement);
      IAddFeature addFeature = featureProvider.getAddFeature(context);

      if (addFeature == null) {
        System.out.println("Element not supported: " + flowElement);
        return;
      }

      GraphicInfo graphicInfo = locationMap.get(flowElement.getId());
      if (graphicInfo == null) {

        noDIList.add(flowElement);

      } else {

        context.setNewObject(flowElement);
        context.setSize((int) graphicInfo.getWidth(), (int) graphicInfo.getHeight());

        ContainerShape parentContainer = null;
        if (parentShape instanceof Diagram) {
          parentContainer = getParentContainer(flowElement.getId(), process, (Diagram) parentShape);
        } else {
          parentContainer = parentShape;
        }

        context.setTargetContainer(parentContainer);
        if (parentContainer instanceof Diagram == false) {
          Point location = getLocation(parentContainer);
          context.setLocation(
              (int) graphicInfo.getX() - location.x, (int) graphicInfo.getY() - location.y);
        } else {
          context.setLocation((int) graphicInfo.getX(), (int) graphicInfo.getY());
        }

        if (flowElement instanceof ServiceTask) {

          ServiceTask serviceTask = (ServiceTask) flowElement;

          if (serviceTask.isExtended()) {

            CustomServiceTask targetTask = findCustomServiceTask(serviceTask);

            if (targetTask != null) {

              for (FieldExtension field : serviceTask.getFieldExtensions()) {
                CustomProperty customFieldProperty = new CustomProperty();
                customFieldProperty.setName(field.getFieldName());
                if (StringUtils.isNotEmpty(field.getExpression())) {
                  customFieldProperty.setSimpleValue(field.getExpression());
                } else {
                  customFieldProperty.setSimpleValue(field.getStringValue());
                }
                serviceTask.getCustomProperties().add(customFieldProperty);
              }

              serviceTask.getFieldExtensions().clear();
            }
          }
        }

        if (flowElement instanceof BoundaryEvent) {
          BoundaryEvent boundaryEvent = (BoundaryEvent) flowElement;
          if (boundaryEvent.getAttachedToRef() != null) {
            ContainerShape container =
                (ContainerShape)
                    featureProvider.getPictogramElementForBusinessObject(
                        boundaryEvent.getAttachedToRef());

            if (container != null) {
              AddContext boundaryContext = new AddContext(new AreaContext(), boundaryEvent);
              boundaryContext.setTargetContainer(container);
              Point location = getLocation(container);
              boundaryContext.setLocation(
                  (int) graphicInfo.getX() - location.x, (int) graphicInfo.getY() - location.y);

              if (addFeature.canAdd(boundaryContext)) {
                PictogramElement newBoundaryContainer = addFeature.add(boundaryContext);
                // featureProvider.link(newBoundaryContainer, new Object[] { boundaryEvent });
              }
            }
          }
        } else if (addFeature.canAdd(context)) {
          PictogramElement newContainer = addFeature.add(context);
          featureProvider.link(newContainer, new Object[] {flowElement});

          if (flowElement instanceof SubProcess) {
            drawFlowElements(
                ((SubProcess) flowElement).getFlowElements(),
                locationMap,
                (ContainerShape) newContainer,
                process);
          }
        }
      }
    }

    for (FlowElement flowElement : noDIList) {
      if (flowElement instanceof BoundaryEvent) {
        ((BoundaryEvent) flowElement).getAttachedToRef().getBoundaryEvents().remove(flowElement);
      } else {
        elementList.remove(flowElement);
      }
    }
  }
  @SuppressWarnings({"rawtypes", "unchecked"})
  protected void drawFlowElements(
      Collection<FlowElement> elementList,
      Map<String, GraphicInfo> locationMap,
      ContainerShape parentShape,
      Process process) {

    final IFeatureProvider featureProvider = getDiagramTypeProvider().getFeatureProvider();

    List<FlowElement> noDIList = new ArrayList<FlowElement>();
    for (FlowElement flowElement : elementList) {

      if (flowElement instanceof SequenceFlow) {
        continue;
      }

      AddContext context = new AddContext(new AreaContext(), flowElement);
      IAddFeature addFeature = featureProvider.getAddFeature(context);

      if (addFeature == null) {
        System.out.println("Element not supported: " + flowElement);
        return;
      }

      GraphicInfo graphicInfo = locationMap.get(flowElement.getId());
      if (graphicInfo == null) {

        noDIList.add(flowElement);

      } else {

        context.setNewObject(flowElement);
        context.setSize((int) graphicInfo.getWidth(), (int) graphicInfo.getHeight());
        ContainerShape parentContainer = null;
        if (parentShape instanceof Diagram) {
          parentContainer = getParentContainer(flowElement.getId(), process, (Diagram) parentShape);
        } else {
          parentContainer = parentShape;
        }

        context.setTargetContainer(parentContainer);
        if (parentContainer instanceof Diagram == false) {
          Point location = getLocation(parentContainer);
          context.setLocation(
              (int) graphicInfo.getX() - location.x, (int) graphicInfo.getY() - location.y);
        } else {
          context.setLocation((int) graphicInfo.getX(), (int) graphicInfo.getY());
        }

        if (flowElement instanceof ServiceTask) {

          ServiceTask serviceTask = (ServiceTask) flowElement;

          if (serviceTask.isExtended()) {

            CustomServiceTask targetTask = findCustomServiceTask(serviceTask);

            if (targetTask != null) {

              for (FieldExtension field : serviceTask.getFieldExtensions()) {
                CustomProperty customFieldProperty = new CustomProperty();
                customFieldProperty.setName(field.getFieldName());
                if (StringUtils.isNotEmpty(field.getExpression())) {
                  customFieldProperty.setSimpleValue(field.getExpression());
                } else {
                  customFieldProperty.setSimpleValue(field.getStringValue());
                }
                serviceTask.getCustomProperties().add(customFieldProperty);
              }

              serviceTask.getFieldExtensions().clear();
            }
          }

        } else if (flowElement instanceof UserTask) {

          UserTask userTask = (UserTask) flowElement;

          if (userTask.isExtended()) {

            CustomUserTask targetTask = findCustomUserTask(userTask);

            if (targetTask != null) {

              final List<Class<CustomUserTask>> classHierarchy =
                  new ArrayList<Class<CustomUserTask>>();
              final List<String> fieldInfoObjects = new ArrayList<String>();

              Class clazz = targetTask.getClass();
              classHierarchy.add(clazz);

              boolean hierarchyOpen = true;
              while (hierarchyOpen) {
                clazz = clazz.getSuperclass();
                if (CustomUserTask.class.isAssignableFrom(clazz)) {
                  classHierarchy.add(clazz);
                } else {
                  hierarchyOpen = false;
                }
              }

              for (final Class<CustomUserTask> currentClass : classHierarchy) {
                for (final Field field : currentClass.getDeclaredFields()) {
                  if (field.isAnnotationPresent(Property.class)) {
                    fieldInfoObjects.add(field.getName());
                  }
                }
              }

              for (String fieldName : userTask.getExtensionElements().keySet()) {
                if (fieldInfoObjects.contains(fieldName)) {
                  CustomProperty customFieldProperty = new CustomProperty();
                  customFieldProperty.setName(fieldName);
                  customFieldProperty.setSimpleValue(
                      userTask.getExtensionElements().get(fieldName).get(0).getElementText());
                  userTask.getCustomProperties().add(customFieldProperty);
                }
              }

              for (String fieldName : fieldInfoObjects) {
                userTask.getExtensionElements().remove(fieldName);
              }
            }
          }
        }

        if (flowElement instanceof BoundaryEvent) {
          BoundaryEvent boundaryEvent = (BoundaryEvent) flowElement;
          if (boundaryEvent.getAttachedToRef() != null) {
            ContainerShape container =
                (ContainerShape)
                    featureProvider.getPictogramElementForBusinessObject(
                        boundaryEvent.getAttachedToRef());

            if (container != null) {
              AddContext boundaryContext = new AddContext(new AreaContext(), boundaryEvent);
              boundaryContext.setTargetContainer(container);
              Point location = getLocation(container);
              boundaryContext.setLocation(
                  (int) graphicInfo.getX() - location.x, (int) graphicInfo.getY() - location.y);

              if (addFeature.canAdd(boundaryContext)) {
                addFeature.add(boundaryContext);
              }
            }
          }
        } else if (addFeature.canAdd(context)) {
          PictogramElement newContainer = addFeature.add(context);
          featureProvider.link(newContainer, new Object[] {flowElement});

          if (flowElement instanceof SubProcess) {
            drawFlowElements(
                ((SubProcess) flowElement).getFlowElements(),
                locationMap,
                (ContainerShape) newContainer,
                process);
          }
        }
      }
    }

    for (FlowElement flowElement : noDIList) {
      if (flowElement instanceof BoundaryEvent) {
        ((BoundaryEvent) flowElement).getAttachedToRef().getBoundaryEvents().remove(flowElement);
      } else {
        // do not remove Data Objects
        if (flowElement instanceof DataObject == false) {
          elementList.remove(flowElement);
        }
      }
    }
  }