Invariants
Object Constraint Language (OCL) is a textual language used for specifying constraints, conditions, and expressions on UML models. OCL invariants are rules and constraints that define conditions that must be true for objects and their relationships within a UML model. Invariants play a crucial role in ensuring the correctness and integrity of a UML model. Here are some critical points about OCL invariants:
- Syntax: OCL invariants are typically expressed using a well-defined syntax. They follow a format similar to predicate logic and often use keywords such as
inv(for invariant) to specify that a condition must hold. - Usage: Invariants can be applied to various elements of a UML model, including classes, associations, attributes, and operations. They provide a way to specify constraints that must be satisfied by instances of these elements.
- Invariant examples:
- Class invariants: You can specify invariants on a UML class to define conditions that should always...
