Description
OCL is a descendant of Syntropy, a second-generation object-oriented analysis and design method. The OCL 1.4 definition specified a constraint language. In OCL 2.0, the definition has been extended to include general object query language definitions.
OCL statements are constructed in four parts:
- a context that defines the limited situation in which the statement is valid
- a property that represents some characteristics of the context (e.g., if the context is a class, a property might be an attribute)
- an operation (e.g., arithmetic, set-oriented) that manipulates or qualifies a property, and
- keywords (e.g., if, then, else, and, or, not, implies) that are used to specify conditional expressions.
Read more about this topic: Object Constraint Language
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