What is an invariant OCL?
What is an invariant OCL?
Object Constraint Language (OCL) Invariant. – Constraint that applies to ALL instances of class (or type or interface) – An expression that evaluates to true if the condition is met. – All Invariants must ALWAYS evaluate to true.
What is OCL as adopted in UML class diagram?
UML provides itself a formal language to express constraints, the Object Constraint Language (OCL) [OMG03]. It is a formal language that can be used to specify invariants, pre- and post- conditions as well as describe guards and constraints on operations. OCL expressions do not have side- effects.
Is OCL a formal language?
OCL has been developed to fill this gap. OCL is a formal language, which remains easy to read and write.
Who developed OCL?
This has resulted in the current UML 1.1 proposal. IBM’s primary contribution to UML 1.1 is OCL. OCL was developed by Jos Warmer as a language for business modelling within IBM, derived from the Syntropy method of Steve Cook and John Daniels.
What is OCL expression?
The Object Constraint Language (OCL) is an expression language that describes constraints on object-oriented languages and other modelling artifacts. A constraint can be seen as a restriction on a model or a system. OCL is the expression language for the Unified Modeling Language (UML).
What is OCL software engineering?
The Object Constraint Language (OCL) is a declarative language describing rules applying to Unified Modeling Language (UML) models developed at IBM and is now part of the UML standard.
Why do we use OCL?
A constraint can be seen as a restriction on a model or a system. OCL is part of Unified Modeling Language (UML) and it plays an important role in the analysis phase of the software lifecycle. languages can use OCL to specify constraints and other expressions attached to their models.
What does OCL stand for?
OCL
Acronym | Definition |
---|---|
OCL | Operations Coordination Letter |
OCL | Office of Congressional Liaisons |
OCL | Obligation Cost Level |
OCL | Optical Carrier Levels |
Why is OCL used?
Object Constraint Language can be used to specify constraints and other expressions attached to UML models or other models. OCL help to create a precise and unambiguous specification in OO modelling. Class Diagram is an example. OCL has its own set of Grammar and rules.