<!-- Spring Data JPA -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

<!-- MySQL驅(qū)動(dòng)（版本需與本地MySQL一致） -->
<dependency>
    <groupId>com.mysql</groupId>
    <artifactId>mysql-connector-j</artifactId>
    <scope>runtime</scope>
</dependency>

<!-- 可選：Lombok簡(jiǎn)化代碼 -->
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

# 數(shù)據(jù)源配置
spring.datasource.url=jdbc:mysql://localhost:3306/springboot_db?useSSL=false&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

# JPA配置
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=true

package com.example.demo.entity;

import jakarta.persistence.*;
import lombok.Data;

@Data
@Entity
@Table(name = "user") // 指定表名
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    @Column(nullable = false, unique = true)
    private String username;
    
    @Column(nullable = false)
    private String password;
    
    private String email;
}

package com.example.demo.repository;

import com.example.demo.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;

public interface UserRepository extends JpaRepository<User, Long> {
    // 自定義查詢(xún)方法（按用戶(hù)名查找）
    User findByUsername(String username);
}

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;

@Service
public class UserService {
    @Autowired
    private UserRepository userRepository;

    public User saveUser(User user) {
        return userRepository.save(user);
    }

    public User findUserByUsername(String username) {
        return userRepository.findByUsername(username);
    }
}

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.web.bind.annotation.*;

@RestController
@RequestMapping("/api/users")
public class UserController {
    @Autowired
    private UserService userService;

    @PostMapping
    public User createUser(@RequestBody User user) {
        return userService.saveUser(user);
    }

    @GetMapping("/{username}")
    public User getUser(@PathVariable String username) {
        return userService.findUserByUsername(username);
    }
}

create table user (
    id bigint not null auto_increment,
    email varchar(255),
    password varchar(255) not null,
    username varchar(255) not null unique,
    primary key (id)
);

{
  "username": "csdn_user",
  "password": "123456",
  "email": "csdn@example.com"
}

GRANT ALL PRIVILEGES ON springboot_db.* TO 'root'@'localhost';
FLUSH PRIVILEGES;