# Spring Mvc

> Skill: spring-mvc

- Skill: `carlnaddy/spring-mvc` (Agent Skill)
- Install (CLI): `npx skillmds@latest add carlnaddy/spring-mvc`
- Raw SKILL.md: https://api.skillmd.com/api/skills/carlnaddy/spring-mvc/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: CarlNaddy (https://skillmd.com/u/carlnaddy)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/carlnaddy/spring-mvc

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# Skill: spring-mvc

## Type
core

## Purpose

Provide server-side rendering using Spring MVC with HTML templates.

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## When to Use

Use when building applications that render HTML on the server.

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## Rules

- Use @Controller (NOT @RestController)
- Return template names (not JSON)
- Use Model to pass data to views
- Prefer immutable web model types; use Java `record` for request/response/view DTOs when mutability is not required
- For `@ModelAttribute`, prefer constructor binding for dedicated web-binding objects

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## Architecture

- Controller → handles HTTP requests
- Service → business logic
- Repository → data access

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## Routing

- Each route returns a full HTML page OR a fragment
- Use clear URL structure (e.g. /users, /users/{id})

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## Web Model Design (Java 17)

- Preferred: Java `record` for immutable web-facing objects (request DTOs, response DTOs, view models, form command objects that are constructor-bound)
- Keep web-binding objects separate from domain/persistence objects
- Use mutable classes only when property mutation is required by the use case
- Do NOT use records for JPA entities that require mutable lifecycle behavior

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## Example

```java
@Controller
@RequestMapping("/users")
public class UserController {

    @GetMapping
    public String list(Model model) {
        model.addAttribute("users", userService.findAll());
        return "users/list";
    }
}
```

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## Defaults

* Template folder: `src/main/resources/templates`
* Naming: feature-based (users/list.html)

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## Anti-Patterns

* Do NOT return JSON
* Do NOT use @RestController
* Do NOT mix REST and MVC