An enumeration is a primitive datatype
that can have a fixed short list of values.
It has no attributes,
and any operations on them must have no
side-effects. A useful analogy is the primitive datatype
boolean in a language like Java.
The boolean stands on its
own -it has no inner structure.
There are operations (for
example logical xor) on the booleans, but when I perform
true xor true the result is a new boolean,
and the original 2 booleans “true”
are unchanged by the exercise.
Within UML 1.4, Enumeration is a
sub-class of the DataType metaclass.
The big difference with other DataTypes, is that an
Enumeration has EnumerationLiterals.
E.g. the Enumeration “boolean” is defined as
having 2 EnumerationLiterals, “true” and
“false”.
Within ArgoUML new enumerations may be created using the
New Enumeration button on the property tabs of
the model and packages (in which case the new enumeration is
restricted in scope to the package), as well as the properties
tab for datatype and enumeration.
Enumerations can also be created with the tool
in the diagram toolbar of a class diagram.
The UML 1.4 standard allows user defined
enumerations to be placed on class diagrams
to define their inheritence structure.
This is also possible in ArgoUML.
It is represented on the diagram by a box
with three compartments,
of which the top one is marked with
«enumeration»,
and contains the name.
The middle compartment shows the enumeration literals.
The lower one contains operations.
The details tabs that are active for enumerations are as follows.
ToDoItemStandard tab.
PropertiesSee Section 16.4.2, “ Enumeration Property Toolbar ” and Section 16.4.3, “ Property Fields For Enumeration ” below.
DocumentationStandard tab. See Section 13.4, “ Documentation Tab ”.
PresentationStandard tab.
SourceStandard tab.
StereotypeStandard tab. The UML metamodel has the following stereotypes defined by default for a Classifier, which also apply to an Enumeration:
metaclass(from the superclass,Classifier).powertype(from the superclass,Classifier).process(from the superclass,Classifier).thread(from the superclass,Classifier).utility(from the superclass,Classifier).
Tagged ValuesStandard tab. In the UML metamodel,
Enumerationhas no standard tagged values defined.
Go upNavigate up through the composition structure.
New datatypeThis creates a new datatype (see Section 18.6, “ Class ”) within the same package as the current enumeration.
New enumerationThis creates a new enumeration within the same namespace as the current enumeration, navigating immediately to the properties tab for new enumeration.
New enumeration literalThis creates a new enumeration literal within the enumeration, navigating immediately to the properties tab for that literal.
New OperationThis creates a new operation within the enumeration, navigating immediately to the properties tab for that operation.
New StereotypeThis creates a new Stereotype (see Section 16.6, “ Stereotype ”) within the same package as the enumeration, navigating immediately to the properties tab for that stereotype.
Delete from ModelThis deletes the datatype from the model.
NameText box. The name of the enumeration. The primitive enumerations all have lower case names, but there is no formal convention.
![[Note]](images/note.png)
Note The default name supplied for a newly created datatype is the empty string “”. Enumerations with empty string names will appear with the name
(Unnamed Enumeration)in the explorer.NamespaceDrop down selector with navigation button. Allows changing the namespace for the enumeration. This is the composition hierarchy.
ModifiersCheck box, with entries
Abstract,LeafandRoot.Abstractis used to declare that this enumeration cannot be instantiated, but must always be specialized.Leafindicates that this enumeration can have no further sub-types, whileRootindicates it is a top level enumeration.
VisibilityRadio box, with entries
public,private,protected, andpackage.Records the visibility for the Enumeration.
Client DependenciesText area. Lists any elements that depend on this enumeration. Button 1 double click navigates to the selected modelelement. Button 2 click brings up a pop up menu with following entry.
Add.... This brings up a dialog box that allows to create dependencies from other modelelements.
Supplier DependenciesText area. Lists any elements that this enumeration depends on. Button 1 double click navigates to the selected modelelement. Button 2 click brings up a pop up menu with the following entry.
Add.... This brings up a dialog box that allows to create dependencies to other modelelements.
GeneralizationsText area. Lists any enumeration that generalizes this enumeration.
SpecializationsText box. Lists any specialized enumerations (i.e. for which this enumeration is a generalization.
OperationsText area. Lists all the operations defined on this enumeration. Button 1 double click navigates to the selected operation. Button 2 click brings up a pop up menu with two entries.
Move Up. Only available where there are two or more operations, and the operation selected is not at the top. It is moved up one.Move Down. Only available where there are two or more operations listed, and the operation selected is not at the bottom. It is moved down one.
See Section 18.8, “ Operation ” for details of operations.
![[Caution]](images/caution.png)
Caution ArgoUML treats all operations as equivalent. Any operations created here will use the same mechanism as operations for classes. Remember that operations on enumerations must have no side effects (they are read-only). This means the
querymodifier must be checked for all operations.LiteralsText area. Lists all the enumeration literals defined for this enumeration. Button 1 double click navigates to the selected literal, button 2 click brings up a pop up menu with two entries.
Move Up. Only available where there are two or more literals, and the literal selected is not at the top. It is moved up one.Move Down. Only available where there are two or more literals listed, and the literal selected is not at the bottom. It is moved down one.