feat: 添加 Swagger 配置与用户 CRUD 接口，集成 MySQL 数据库

Co-authored-by: aider (openai/deepseek-v4-pro) <aider@aider.chat>

pom.xml

@@ -35,6 +35,26 @@
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
         </dependency>
+
+        <!-- Spring Data JPA -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-jpa</artifactId>
+        </dependency>
+
+        <!-- MySQL 驱动 -->
+        <dependency>
+            <groupId>mysql</groupId>
+            <artifactId>mysql-connector-java</artifactId>
+            <scope>runtime</scope>
+        </dependency>
+
+        <!-- SpringDoc OpenAPI (Swagger) -->
+        <dependency>
+            <groupId>org.springdoc</groupId>
+            <artifactId>springdoc-openapi-ui</artifactId>
+            <version>1.6.14</version>
+        </dependency>
     </dependencies>
 
     <build>

src/main/java/com/example/demo/config/SwaggerConfig.java

@@ -0,0 +1,19 @@
+package com.example.demo.config;
+
+import io.swagger.v3.oas.models.OpenAPI;
+import io.swagger.v3.oas.models.info.Info;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class SwaggerConfig {
+
+    @Bean
+    public OpenAPI customOpenAPI() {
+        return new OpenAPI()
+                .info(new Info()
+                        .title("Demo API")
+                        .version("1.0")
+                        .description("用户信息管理接口"));
+    }
+}

src/main/java/com/example/demo/controller/UserController.java

@@ -0,0 +1,56 @@
+package com.example.demo.controller;
+
+import com.example.demo.entity.User;
+import com.example.demo.service.UserService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+
+@RestController
+@RequestMapping("/users")
+public class UserController {
+
+    @Autowired
+    private UserService userService;
+
+    @GetMapping
+    public List<User> list() {
+        return userService.findAll();
+    }
+
+    @GetMapping("/{id}")
+    public ResponseEntity<User> getById(@PathVariable Long id) {
+        return userService.findById(id)
+                .map(ResponseEntity::ok)
+                .orElse(ResponseEntity.notFound().build());
+    }
+
+    @PostMapping
+    public User create(@RequestBody User user) {
+        return userService.save(user);
+    }
+
+    @PutMapping("/{id}")
+    public ResponseEntity<User> update(@PathVariable Long id, @RequestBody User user) {
+        return userService.findById(id)
+                .map(existing -> {
+                    existing.setName(user.getName());
+                    existing.setEmail(user.getEmail());
+                    existing.setAge(user.getAge());
+                    return ResponseEntity.ok(userService.save(existing));
+                })
+                .orElse(ResponseEntity.notFound().build());
+    }
+
+    @DeleteMapping("/{id}")
+    public ResponseEntity<Void> delete(@PathVariable Long id) {
+        if (userService.findById(id).isPresent()) {
+            userService.deleteById(id);
+            return ResponseEntity.noContent().build();
+        } else {
+            return ResponseEntity.notFound().build();
+        }
+    }
+}

src/main/java/com/example/demo/entity/User.java

@@ -0,0 +1,61 @@
+package com.example.demo.entity;
+
+import javax.persistence.*;
+
+@Entity
+@Table(name = "t_user")
+public class User {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(nullable = false)
+    private String name;
+
+    @Column(nullable = false)
+    private String email;
+
+    private Integer age;
+
+    public User() {
+    }
+
+    public User(String name, String email, Integer age) {
+        this.name = name;
+        this.email = email;
+        this.age = age;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public Integer getAge() {
+        return age;
+    }
+
+    public void setAge(Integer age) {
+        this.age = age;
+    }
+}

src/main/java/com/example/demo/repository/UserRepository.java

@@ -0,0 +1,9 @@
+package com.example.demo.repository;
+
+import com.example.demo.entity.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface UserRepository extends JpaRepository<User, Long> {
+}

src/main/java/com/example/demo/service/UserService.java

@@ -0,0 +1,32 @@
+package com.example.demo.service;
+
+import com.example.demo.entity.User;
+import com.example.demo.repository.UserRepository;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+import java.util.Optional;
+
+@Service
+public class UserService {
+
+    @Autowired
+    private UserRepository userRepository;
+
+    public List<User> findAll() {
+        return userRepository.findAll();
+    }
+
+    public Optional<User> findById(Long id) {
+        return userRepository.findById(id);
+    }
+
+    public User save(User user) {
+        return userRepository.save(user);
+    }
+
+    public void deleteById(Long id) {
+        userRepository.deleteById(id);
+    }
+}

src/main/resources/application.yml

@@ -1,2 +1,16 @@
 server:
   port: 8080
+
+spring:
+  datasource:
+    url: jdbc:mysql://localhost:3306/demo?useSSL=false&characterEncoding=utf8&serverTimezone=UTC
+    username: root
+    password: 123456
+    driver-class-name: com.mysql.cj.jdbc.Driver
+  jpa:
+    hibernate:
+      ddl-auto: update
+    show-sql: true
+    properties:
+      hibernate:
+        dialect: org.hibernate.dialect.MySQL8Dialect