ModelElementTypeBuilder typeBuilder = modelBuilder.defineType(Activity.class, BPMN_ELEMENT_ACTIVITY)
.namespaceUri(BpmnModelConstants.BPMN20_NS)
.extendsType(FlowNode.class)
.abstractType();
isForCompensationAttribute = typeBuilder.booleanAttribute(BPMN_ATTRIBUTE_IS_FOR_COMPENSATION)
.defaultValue(false)
.build();
startQuantityAttribute = typeBuilder.integerAttribute(BPMN_ATTRIBUTE_START_QUANTITY)
.defaultValue(1)