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The ObjectModel metamodel contains the data types, listed below in alphabetical order. Each of these data types is an instance
of the DataType class.
Some of these data types have default values. These default values only apply for mandatory attributes or parameters of the
relevant data type where an explicit value is not supplied.
Any
The Any data type is used to indicate that an attribute or parameter may take values from any of the available data types.
In CWM, the set of data types an Any attribute or parameter may assume includes the data types and enumerations described
in this chapter plus any available instances of the Classifier class.
There is no default value for data type Any.
Boolean
Boolean defines an enumeration that denotes a logical condition. Its enumeration literals are:
• true - The Boolean condition is satisfied.
• false -The Boolean condition is not satisfied.
The default for data type Boolean is false.
Float
The Float data type is used to indicate that an attribute or parameter may take on floating point numeric values. The number
of significant digits and other representational details are implementation defined.
The default for the Float data type is the value 0.0.
Integer
Integer represents the predefined type of integers. An instance of Integer is an element in the (infinite) set of integers
(…-2, -1, 0, 1, 2…).
The default for Integer is 0.
Name
Name defines a token that is used for naming ModelElements and similar usages. Each Name has a corresponding String representation.
For purposes of exchange a name should be represented as a String.
The default for the Name data type is an empty string.
String
String defines a piece of text. Strings do not normally have a defined length; rather, they are considered to be arbitrarily
long (practical limits on the length of Strings exist, but are implementation dependent). When String is used as the type
of an Attribute, string length sometimes can be specified (see the Relational and Record packages for examples).
The default for the String data type is an empty string.
Time
Time defines a statement that will define the time of occurrence of an event. The specific format of time expressions is not
specified here and is subject to implementation considerations.
There is no default for the Time data type.
UnlimitedInteger
UnlimitedInteger defines a data type whose range is the nonnegative integers augmented by the special value “unlimited.? It
is used for the upper bound of multiplicities.
The default for an UnlimitedInteger is the special value “unlimited.?
The ObjectModel metamodel contains the enumerated data types shown below in alphabetical order. Enumeration literals defined
for each enumerated type are described as well.
ChangeableKind
In the metamodel ChangeableKind defines an enumeration that denotes how an attribute link may be modified. Its values are:
• ck_changeable - No restrictions on modification.
• ck_frozen - The value may not be changed from the source end after the creation and initialization of the source object. Operations on the other end may change a value.
• ck_addOnly - If the multiplicity is not fixed, values may be added at any time from the source object, but once created a value may not be removed from the source end. Operations on the other end may change a value.
The default value is ck_changeable.
OrderingKind
In the metamodel OrderingKind defines an enumeration that specifies how the elements of a set are arranged. Used in conjunction
with elements that have a multiplicity in cases when the multiplicity value is greater than one. The ordering must be determined
and maintained by operations that modify the set. Its values are:
• ok_unordered - The elements of the set have no inherent ordering.
• ok_ordered - The elements of the set have a sequential ordering.
The default value is ok_unordered.
ScopeKind
In the metamodel ScopeKind defines an enumeration that denotes whether a feature belongs to individual instances or an entire
classifier. Its values are:
• sk_instance - The feature pertains to instances of a Classifier. For example, it is a distinct attribute in each instance or an operation that works on an instance.
• sk_classifier - The feature pertains to an entire Classifier. For example, it is an attribute shared by the entire Classifier or an operation that works on the Classifier, such as a creation operation.
The default value is sk_instance.
VisibilityKind
In the metamodel VisibilityKind defines an enumeration that denotes how the element to which it refers is seen outside the
enclosing name space. Its values are:
• vk_public - Other elements may see and use the target element.
• vk_protected - Descendants of the source element may see and use the target element.
• vk_private - Only the source element may see and use the target element.
• vk_package - Elements declared in the same package as the target element may see and use the target element.
• vk_notapplicable -May be used where namespaces do not support the concept of visibility.
The default value is vk_public.