在 Spring Boot 中连接 MySQL 数据库的详细步骤

<dependencies>
    <!-- Spring Boot Starter Data JPA -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <!-- MySQL Driver -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <scope>runtime</scope>
    </dependency>
</dependencies>

# 数据库连接配置
spring.datasource.url=jdbc:mysql://localhost:3306/your_database_name?useSSL=false&serverTimezone=UTC
spring.datasource.username=your_username
spring.datasource.password=your_password
# JPA 配置
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=true

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/your_database_name?useSSL=false&serverTimezone=UTC
    username: your_username
    password: your_password
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true
    properties:
      hibernate:
        format_sql: true

package com.example.demo.model;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
@Entity
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;
    private String email;
    // Getters and Setters
    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;
    }
}

package com.example.demo.repository;
import com.example.demo.model.User;
import org.springframework.data.jpa.repository.JpaRepository;
public interface UserRepository extends JpaRepository<User, Long> {
}

package com.example.demo.service;
import com.example.demo.model.User;
import com.example.demo.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class UserService {
    @Autowired
    private UserRepository userRepository;
    public List<User> getAllUsers() {
        return userRepository.findAll();
    }
    public User getUserById(Long id) {
        return userRepository.findById(id).orElse(null);
    }
    public User saveUser(User user) {
        return userRepository.save(user);
    }
    public void deleteUser(Long id) {
        userRepository.deleteById(id);
    }
}

package com.example.demo.controller;
import com.example.demo.model.User;
import com.example.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
@RestController
@RequestMapping("/users")
public class UserController {
    @Autowired
    private UserService userService;
    @GetMapping
    public List<User> getAllUsers() {
        return userService.getAllUsers();
    }
    @GetMapping("/{id}")
    public User getUserById(@PathVariable Long id) {
        return userService.getUserById(id);
    }
    @PostMapping
    public User createUser(@RequestBody User user) {
        return userService.saveUser(user);
    }
    @PutMapping("/{id}")
    public User updateUser(@PathVariable Long id, @RequestBody User user) {
        user.setId(id);
        return userService.saveUser(user);
    }
    @DeleteMapping("/{id}")
    public void deleteUser(@PathVariable Long id) {
        userService.deleteUser(id);
    }
}

mvn spring-boot:run

    {
      "name": "John Doe",
      "email": "john.doe@example.com"
    }
    ```
• 更新用户：
• PUT`http://localhost:8080/users/{id}`
• Body:
```json
    {
      "name": "Jane Doe",
      "email": "jane.doe@example.com"
    }