Library Catalog Items Example | AI Sequence Diagram Refinement Tool

In a library environment, the catalog is the backbone that connects readers with books and resources. The Catalog Items use case illustrates how a librarian or patron views, validates, and manages catalog records. Using the Sequence Diagram Refinement Tool, this everyday interaction can be transformed into an MVC sequence diagram that highlights how the user interface communicates with the underlying catalog services.

01 | Diagram Input

Begin by entering your sequence diagram code (Mermaid or PlantUML) that represents catalog operations, such as displaying items or submitting forms. You can also start fresh by generating one with the MVC System Architecture Generator instead of writing it manually.

Sequence Diagram PlantUML Example:

@startuml

actor Librarian
participant "Catalog View" as View
participant "Catalog Controller" as Controller
participant "Catalog Model" as Model

Librarian -> View: Open "Catalog Items"
View -> Controller: Request form
Controller -> View: Show form
Librarian -> View: Fill form + Save
View -> Controller: Submit data
Controller -> Model: Save record
Model --> Controller: Success / Error
Controller --> View: Show result

Librarian -> View: Select "Edit"
View -> Controller: Load record
Controller -> Model: Fetch record
Model --> Controller: Record data
Controller --> View: Show data
Librarian -> View: Update + Save
View -> Controller: Submit changes
Controller -> Model: Update record
Model --> Controller: Success / Conflict
Controller --> View: Show result

Librarian -> View: Select "Delete"
View -> Librarian: Confirm?
alt Confirmed
Librarian -> Controller: Delete request
Controller -> Model: Delete record
Model --> Controller: Success / Fail
Controller --> View: Show result
else Cancelled
View --> Librarian: Abort
end

@enduml

02 | Rendered Sequence Diagram

Once you click Render Diagram, the tool visualizes your catalog sequence. At this stage, you may save the preview as an SVG or open it inside Visual Paradigm Online for adjustments. To move into AI-powered refinement, simply proceed with Decompose Layers.

03 | Decomposed Architecture Layers

The AI examines the interactions and organizes them into distinct roles. For this case, it might identify:

• View Objects: CatalogViewController, FormRenderer, FormValidator, …
• Model Objects: CatalogRepository, CatalogService, PersistenceLayer, …

04 | Detailed MVC Sequence Diagram

A more elaborate sequence diagram is then generated, showing how forms and views coordinate with backend services and the persistence layer. This refined version can be exported in SVG format or further shaped in Visual Paradigm Online’s editor.