A.2 Metamodel for UML 2.x

Attribute	Type	Multi.	Description
context	ref	one	Owner of the element in the UML model.
id	data	one	Unique identifier of the model element.
name	data	one	Name of the element in UML model.
comments	ref	many	The comments for the model element.

Table 8: Default attributes for the UML2.x metamodel

Table 9 lists all elements of the UML2.x metamodel, and the attributes they define in addition to those inherited from the parent.

Model Element	Attribute	Type	Multi.	Description
class	visibility	data	one	Visibility of the element (public, protected, package, private).
	abstract	data	one	Boolean indicating if the element is abstract.
	leaf	data	one	Boolean indicating if the element can have specializations.
	ownedattributes	ref	many	The attributes of the element.
	ownedoperations	ref	many	The operations of the element.
	nestedclassifiers	ref	many	The nested classifiers of the element.
	generalizations	ref	many	The generalizations owned by the element.
	interfacerealizations	ref	many	The interface realizations owned by the element.
	connectors	ref	many	The connectors owned by the element.
interface	ownedattributes	ref	many	The attributes of the interface.
	ownedoperations	ref	many	The operations of the interface.
	nestedclassifiers	ref	many	The nested classifiers of the interface.
	generalizations	ref	many	The generalizations owned by the interface.
datatype	ownedattributes	ref	many	The attributes of the element.
	ownedoperations	ref	many	The operations of the element.
	generalizations	ref	many	The generalizations owned by the element.
enumeration (extends datatype)	ownedliterals	ref	many	The literals of the enumeration.
enumerationliteral	---	---	---
primitivetype (extends datatype)	---	---	---
connector	ends	ref	many	The connector ends of the connector.
connectorend	role	ref	one	The element that is attached at this connector end.
property	visibility	data	one	Visibility of the feature (public, private, protected, package).
	propertytype	ref	one	Reference to the feature type (class, data type etc).
	isreadonly	data	one	Changeability of the feature. Values: true, false (default if not specified).
	association	ref	one	Reference to association if this is an association end.
	aggregation	data	one	The aggregation kind of the property: shared, composite, or none (default).
	qualifiers	ref	many	The qualifier attributes of the property.
port (extends property)	---	---	---
operation	visibility	data	one	Visibility of the operation (public, private, protected, package).
	abstract	data	one	Boolean indicating if operation is abstract.
	isquery	data	one	Boolean indicating if operation is a query that does not change the classifier's state.
	ownedparameters	ref	many	The parameters of the operation.
parameter	kind	data	one	The direction of the parameter: in (default), out, inout, return.
	parametertype	ref	one	Reference to the parameter type (class, data type etc).
method	---	---	---
package	ownedmembers	ref	many	The owned member elements.
model (extends package)	---	---	---
association	memberends	ref	many	The member ends of the association.
	ownedends	ref	many	The owned ends of the association (not navigable association ends).
	generalizations	ref	many	The generalizations owned by the association.
associationclass (extends association)	---	---	---
generalization	general	ref	one	Link to the parent in the generalization.
interfacerealization	contract	ref	one	Link to the realized interface.
dependency	supplier	ref	many	Links to the supplier elements of the relationship.
	client	ref	many	Links to the client elements of the relationship.
abstraction (extends dependency)	---	---	---
realization (extends abstraction)	---	---	---
substitution (extends realization)	---	---	---
usage (extends dependency)	---	---	---
collaboration (extends class)	ownedbehaviors	ref	many	Behavior specifications owned by the collaboration.
interaction (extends class)	lifelines	ref	many	The lifelines involved in the interaction.
	messages	ref	many	The messages sent within the interaction.
	fragments	ref	many	The message occurrence specifications and combined fragments of the interaction.
instancespecification	classifier	ref	many	Links to the classifiers that this entity is an instance of.
	deployments	ref	many	The deployments where this instance specification is the target.
lifeline	represents	ref	one	The interaction participant that this lifeline represents.
message	receiveevent	ref	one	Occurrence specification for the message reception.
	sendevent	ref	one	Occurrence specification for the message sending.
	sort	data	one	The sort of communication (synchCall, asynchCall, asynchSignal, etc.).
occurrencespec	covered	ref	one	The lifeline on which this occurrence specification appears.
	kind	data	one	The type of this occurrence specification (execution, message, destruction) (since UML2.4).
	event	ref	one	The occurring event (up to UML2.3).
combinedfragment	operator	data	one	The interaction operator (alt, loop, break, opt, par, ref, etc.)
	covered	ref	many	The lifelines covered by this combined fragment.
	operands	ref	many	The interaction operands of this combined fragment.
interactionoperand	fragments	ref	many	The message occurrence specifications and combined fragments of the interaction operand.
actor (extends class)	---	---	---
usecase (extends class)	includes	ref	many	The include relationships owned by the use case.
	extends	ref	many	The extend relationships owned by the use case.
	extensionpoints	ref	many	The extension points owned by the use case.
extensionpoint	---	---	---
usecaseextend	extendedcase	ref	one	The use case that is extended.
	usecaseextensionpoint	ref	one	The extension point in the extended use case.
usecaseinclude	usecaseaddition	ref	one	The included use case.
statemachine	regions	ref	many	The top-level regions owned by the state machine.
	isprotocol	data	one	Boolean indicating if this is a protocol state machine
	connectionpoints	ref	many	The connection points of the state machine.
region	subvertices	ref	many	The states contained in the region.
	transitions	ref	many	The transitions contained in the region.
state	kind	data	one	The kind of state: '' (empty), final, initial, deepHistory, shallowHistory, join, fork, choice, junction, entryPoint, exitPoint, terminate.
	regions	ref	many	The regions of the composite or concurrent state.
	entry	ref	many	The entry activities of the state.
	exit	ref	many	The exit activities of the state.
	doactivity	ref	many	The do-activities of the state.
	connectionpoints	ref	many	The connection points of the state.
transition	kind	data	one	The kind of transition: external, internal, or local.
	isprotocol	data	one	Boolean indicating if this is a protocol transition.
	transsource	ref	one	The source state of the transition.
	transtarget	ref	one	The target state of the transition.
	triggers	ref	many	The triggers that may fire the transition.
	guard	ref	one	The guard of the transition.
	effect	ref	one	The activity to be performed when the transition fires.
constraint	---	---	---
trigger	event	ref	one	The event causing the trigger.
event	kind	data	one	The kind of event (signal, call, change, time, anyreceive).
	linkedeventelement	ref	one	The element (signal, operation, boolean expression, or deadline) that raised the event, if any.
activity	nodes	ref	many	The action, control, and object nodes of the activity.
	edges	ref	many	The control and object flows of the activity.
	groups	ref	many	The groups of the activity.
activitygroup	edges	ref	many	The contained edges of the group.
	nodes	ref	many	The contained nodes of the group.
	groups	ref	many	The subgroups of the group.
	handlers	ref	many	The exception handlers of the structured node group.
	pins	ref	many	Pins owned by the activity group.
	kind	data	one	The kind of group: partition, interruptible, expansion, structured, conditional, loop, sequence.
action	kind	data	one	The kind of action: send, return, create, etc (there are many).
	inputs	ref	many	The input pins of the action.
	outputs	ref	many	The output pins of the action.
	handlers	ref	many	The exception handlers owned by the action.
controlnode	kind	data	one	The kind of control node: initial, activityfinal, flowfinal, fork, join, merge, or decision.
objectnode	kind	data	one	The kind of object node: centralbuffer, datastore, activityparameter, or expansion.
pin	kind	data	one	The kind of pin (input, output, value, actioninput).
	type	ref	one	The type of the pin.
controlflow	source	ref	one	Source of the control flow.
	target	ref	one	Target of the control flow.
	guard	ref	one	Guard of the control flow.
objectflow	source	ref	one	Source of the object flow.
	target	ref	one	Target of the object flow.
	guard	ref	one	Guard of the control flow.
signal	---	---	---
exceptionhandler	handlerbody	ref	one	The node that handles the exception.
	exceptioninput	ref	one	The input node of the handler body that received the exception token.
reception	signal	ref	one	Signal handled by this reception.
expression	---	---	---
opaqueexpression	---	---	---
instancevalue	---	---	---
literalboolean	---	---	---
literalinteger	---	---	---
literalreal	---	---	---
literalstring	---	---	---
literalunlimitednatural	---	---	---
literalnull	---	---	---
component (extends class)	realizations	ref	many	The realizations owned by the component.
	members	ref	many	Other members owned by the component.
node (extends class)	nestednodes	ref	many	The subnodes located on the node.
	deployments	ref	many	The deployment links owned by the node (=deployment location).
	kind	data	one	The type of node (regular, executionenvironment, device)
artifact (extends class)	nestedartifacts	ref	many	The artifacts that are defined (nested) within the artifact.
	manifestations	ref	many	The manifestation links to the model elements that are manifested in the artifact.
deploymentspec (extends artifact)	---	---	---
deployment (extends dependency)	configurations	ref	many	The deployment specifications that parameterize the deployment.
manifestation (extends abstraction)	---	---	---
stereotype	---	---	---
comment	body	data	one	The comment text.
diagram	type	data	one	The type of diagram (class diagram, sequence diagram, etc).
diagramelement	element	ref	one	The element that is shown on the diagram.

Table 9: SDMetrics metamodel elements and attributes for UML2.x models