基于SpringBoot的MybatisPlus简明教程

Posted 2022-01-13 算法与编程之美

目标

• 利用MybatisPlus提供的IService接口和ServiceImpl类更方便的创建自定义Service;

方法

• 创建UserService接口并继承在IService;

import com.baomidou.mybatisplus.extension.service.IService;
import edu.sctu.demo.mybatis.plus.model.UserEntity;

public interface UserService extends IService<UserEntity> 

• 创建接口的实现类UserServiceImpl；

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import edu.sctu.demo.mybatis.plus.mapper.UserMapper;
import edu.sctu.demo.mybatis.plus.model.UserEntity;
import edu.sctu.demo.mybatis.plus.service.UserService;
import org.springframework.stereotype.Service;

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, UserEntity>
        implements UserService 

• 使用UserService提供的更加丰富的功能；

@SpringBootApplication
public class Application implements CommandLineRunner 

    @Autowired(required = false)
    private UserMapper userMapper;

    @Autowired
    private UserService userService;

    public static void main(String[] args) 
        SpringApplication.run(Application.class, args);
    


    @Override
    public void run(String... args) throws Exception 
        System.out.println(userMapper.selectList(null));

        // 带条件的查询
        QueryWrapper<UserEntity> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq("username", "chen");
        System.out.println(userMapper.selectList(queryWrapper));


        System.out.println(userService.count());

    

结语

本文介绍了利用MybatisPlus提供的IService接口以及ServiceImpl通用类提供的丰富的方法，更加便捷的用于操作数据库。