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Classifier (from Kernel , Dependencies , PowerTypes ) on page 51.
A data type is a type whose instances are identified only by their value. A DataType may contain attributes to support the
modeling of structured data types.
A typical use of data types would be to represent programming language primitive types or CORBA basic types. For example,
integer and string types are often treated as data types.
No additional attributes
Issue 7939 -The associations ownedAttribute and ownedOperation are ordered collections.
• ownedAttribute: Property[*] The Attributes owned by the DataType . This is an ordered collection. Subsets Classifier::attribute
and Element::ownedMember
• ownedOperation: Operation[*] The Operations owned by the DataType . This is an ordered collection. Subsets Classifier::feature
and Element::ownedMember
No additional constraints
A data type is a special kind of classifier, similar to a class. It differs from a class in that instances of a data type
are identified only by their value.
All copies of an instance of a data type and any instances of that data type with the same value are considered to be the
same instance. Instances of a data type that have attributes (i.e., is a structured data type) are considered to be the same
if the structure is the same and the values of the corresponding attributes are the same. If a data type has attributes, then
instances of that data type will contain attribute values matching the attributes.
Any restrictions on the capabilities of data types, such as constraining the types of their attributes, is a semantic variation
point.
A data type is denotated using the rectangle symbol with keyword «dataType» or, when it is referenced by (e.g., an attribute)
denoted by a string containing the name of the data type.
Examples
size: Integer
Figure 7.36 - Notation of data type: to the left is an icon denoting a data type and to the right is a reference to a data
type that is used in an attribute.