1. service和impl

package com.gblfy.springboot.mybatisplus.service;import com.baomidou.mybatisplus.extension.service.IService;
import com.gblfy.springboot.mybatisplus.entity.User;public interface UserService extends IService<User> {
}

impl

package com.gblfy.springboot.mybatisplus.service.impl;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.gblfy.springboot.mybatisplus.entity.User;
import com.gblfy.springboot.mybatisplus.mapper.UserMapper;
import com.gblfy.springboot.mybatisplus.service.UserService;
import org.springframework.stereotype.Service;@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {//    源码分析：
//    public class ServiceImpl<M extends BaseMapper<T>, T> implements IService<T> {}

2. 实战

package com.gblfy.springboot.mybatisplus.mapper;import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.toolkit.Wrappers;
import com.gblfy.springboot.mybatisplus.entity.User;
import com.gblfy.springboot.mybatisplus.service.UserService;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest
@Slf4j
public class CommonServiceTest {@Autowiredprivate UserService userService;@Testpublic void getOne() {User one = userService.getOne(Wrappers.<User>lambdaQuery().gt(User::getAge, 25), false);System.out.println(one);}/*** 当调用saveBatch方法会执行插入操作* 当调用saveOrUpdateBatch方法会不存在执行插入存在执行更新操作*/@Testpublic void bath() {User user1 = new User();user1.setName("yuxin");user1.setAge(2);User user2 = new User();user2.setId(11L);user2.setName("ly");user2.setAge(25);List<User> userList = Arrays.asList(user1, user2);
//        boolean saveBatch = userService.saveBatch(userList);boolean saveBatch = userService.saveOrUpdateBatch(userList);System.out.println(saveBatch);}@Testpublic void chain() {List<User> userList = userService.lambdaQuery().gt(User::getAge, 25).like(User::getName, "雨").list();userList.forEach(System.out::println);}@Testpublic void chain2() {boolean update = userService.lambdaUpdate().eq(User::getAge, 25).set(User::getAge, 30).update();System.out.println(update);}@Testpublic void chain3() {boolean remove = userService.lambdaUpdate().eq(User::getAge, 25).remove();System.out.println(remove);}
}