Guide
Mermaid Class Diagram Examples
Show the domain relationship a reviewer needs; avoid copying every field and method from an implementation.
This technical source review checks guide claims against current standards, official documentation, and the behavior of DevPouch tools. It is not an independent security audit.
Related tools
Practical recommendation
Class diagrams are useful for domain discussions and API model reviews when they emphasize responsibilities and relationships.
Prefer a small stable subset of properties. If generated code is the authority, link to it and treat the diagram as an explanatory view.
Working example
classDiagram
class Order {
+string id
+OrderStatus status
+total() number
}
class OrderItem {
+string sku
+number quantity
}
Order "1" *-- "1..*" OrderItem : containsReview checklist
- Relationship direction and cardinality are intentional.
- Public versus private members use the chosen convention consistently.
- Enums and value objects are not mistaken for services.
- The diagram remains a view, not a second source of truth.
Compatibility, security, and limitations
- Mermaid class syntax is not a full UML implementation.
- Language-specific generics and annotations may need prose.
- Avoid exposing private system structure in public documentation.
Choose the question the model answers
A domain review may need aggregate ownership and cardinality; an SDK review may need public properties and interfaces. Mixing database tables, domain objects, transport schemas, and services in one unlabeled class diagram creates false equivalence. State the viewpoint and omit members that do not help that audience.
Use composition, aggregation, inheritance, and dependency intentionally. Cardinalities should match business rules and nullable relationships. If the source code or OpenAPI document is authoritative, link it and date the diagram rather than maintaining an unverified duplicate specification.
Change review
- A required property becomes optional or the reverse.
- Cardinality changes at either end of a relationship.
- An enum gains or removes a value.
- Ownership moves between aggregates or services.
- Generated code and diagram disagree after a contract update.
- The public diagram reveals internal structure that should remain private.
References
FAQ
How should I verify the examples in Mermaid Class Diagram Examples?
Load the synthetic example into the linked DevPouch tool, confirm the visible result, then verify syntax and behavior in the exact platform that will consume it.
Can the generated result replace technical review?
No. Rendering and validation catch mechanical issues; meaning, accessibility, security, and contract accuracy still require human review.