Class Invariants
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What is Class Invariants?
A class invariant is a set of conditions that must be true for any object of a class, at any point in time. In object-oriented programming (OOP), class invariants are used to define the valid states of an object and to ensure that the object always remains in a valid state.
Class invariants are typically defined in the constructor of a class and are enforced through the use of private methods and data members that are used to validate the state of the object. They are also checked in the class's methods before and after any operation that can change the state of the object.
Free resources to learn Class Invariants
More in stage 7: Messaging
- Messaging
- GoF Design Patterns
- PoSA Patterns
- Composition over Inheritance
- Encapsulate what varies
- Program against abstractions
- Domain Models
- Anemic Models
- Domain Language
- Layered Architectures
- Event-Driven
- Client-Server
- Publish-Subscribe
- Peer-to-Peer
- Component Principles
- Policy vs Detail
- Coupling and Cohesion
- Boundaries
Class Invariants: common questions
Can I learn Class Invariants in Hindi?
This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Class Invariants in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.
Is this Class Invariants tutorial for beginners?
It is lesson 55 of 94 in the free Software Design and Architecture roadmap, in stage 7, Messaging. If you are new to Software Design and Architecture, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.