SpringStudy/mybatisPlus_study/src/test/java/cc/bnblogs/mybatis_study/MybatisStudyApplicationTests.java

package cc.bnblogs.mybatis_study;

import cc.bnblogs.mybatis_study.mapper.UserMapper;
import cc.bnblogs.mybatis_study.pojo.User;
import cc.bnblogs.mybatis_study.service.UserService;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.conditions.update.UpdateWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import org.junit.jupiter.api.Test;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@SpringBootTest
class MybatisStudyApplicationTests {

    @Autowired
    private UserMapper userMapper;
    @Autowired
    private UserService service;

    @Test
    public void testSelect() {
        List<Long> list = new ArrayList<>();
        list.add(1L);
        list.add(3L);
        list.add(5L);
        userMapper.deleteBatchIds(list);
        // 查询表中所有数据
        List<User> userList = userMapper.selectList(null);
        userList.forEach(System.out::println);
    }

    @Test
    public void insertTest() {
        User u = new User(1, "aaa", 19, "111@qq.com");
        userMapper.updateById(u);
    }

    @Test
    void simpleSelect() {
        System.out.println("service.count() = " + service.count());
        System.out.println("service.list() = " + service.list());
        System.out.println("service.listMaps() = " + service.listMaps());
        System.out.println("service.listObjs() = " + service.listObjs());
        System.out.println("service.getById(1580903310957416450L) = " + service.getById(1580903310957416450L));
    }

    @Test
    void insertData() {
        // 存入一个user
        User user = new User(null, "zzz", 18, "aa");
//        service.save(user);
        // 批量存入
        List<User> list = new ArrayList<>();
        list.add(user);
        list.add(user);
        list.add(user);
        service.saveBatch(list);
        // 查看所有数据
        service.list().forEach(System.out::println);
    }

    @Test
    void insertUpdate() {
        System.out.println("service.list() = " + service.list());
        User user = new User(null, "9999", 20, "xxx@qq.com");
        // 根据主键进行插入或者更新某条记录，如果数据库中不存在这个主键，那么将会进行插入；
        // 如果存在这个主键，就进行更新这条记录
        service.saveOrUpdate(user);
        System.out.println("service.list() = " + service.list());
    }

    @Test
    void insertBatch() {
        service.list().forEach(System.out::println);
    }

    @Test
    void select() {
        System.out.println("service.count() = " + service.count());
        System.out.println("service.list() = " + service.list());
        System.out.println("service.listMaps() = " + service.listMaps());
        System.out.println("service.listObjs() = " + service.listObjs());
        System.out.println("service.getById(1) = " + service.getById(1));
    }

    @Test
    void test() {
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.ge("id", 5)
                .or(qw -> qw.ge("age",25).le("age",100));
//         小于
//        queryWrapper.lt("id", 3);

//        小于等于
//        queryWrapper.le("id", 3);

//        大于
//        queryWrapper.gt("id", 2);

//        大于等于
//        queryWrapper.ge("id", 3);

//        等于
//        queryWrapper.eq("id", 3);

//        不等于
//        queryWrapper.ne("id", 2);

//        联合起来写，代表大于等于2且小于等于5，且不等于3
//        queryWrapper.ge("id", 2)
//                        .le("id", 5)
//                                .ne("id", 3);

//        between条件
//        queryWrapper.between("id", 2, 4); // id在2到4

//        like条件
//        queryWrapper.like("name", "J%");

//        not like
//        queryWrapper.notLike("name", "%a%");

//        查询某几个字段
//        queryWrapper.select("id", "name");

        /*
        也可以使用group by，select中也可以写别名
        */
//        queryWrapper.groupBy("age");
//        queryWrapper.select("age 年龄", "count(*) 数量");
//        queryWrapper.select("age as 年龄", "count(*) as 数量");

//        in的用法
//        queryWrapper.in("id", 2, 3, 4);
//        queryWrapper.in("id", List.of(2, 3, 4));

//        not in
//        queryWrapper.notIn("id", 2, 3, 5);
//        queryWrapper.notIn("id", List.of(2, 3, 5)); // jdk 9新API

//        排序
//        正序
//        queryWrapper.orderBy(true, true, "id");
//        queryWrapper.orderByAsc("id");
//        倒序
//        queryWrapper.orderBy(true, true, "id");
//        queryWrapper.orderByDesc("id");

//        ((id >= ?) OR (age >= ? AND age <= ?))
//        queryWrapper.ge("id", 5)
//                .or()
//                .ge("age", 25)
//                .le("age", 100);


//        queryWrapper.ge("id", 5)
//                .or(wrapper -> wrapper.ge("age", 25).le("age", 100));

//                queryWrapper.isNull("列名").isNotNull("列名")
        userMapper.selectList(queryWrapper).forEach(System.out::println);
    }


    @Test
    void delete() {
        service.removeById(1);
        List<Integer> list = new ArrayList<>();
        list.add(1);
        list.add(2);
        list.add(3);
        service.removeByIds(list);
        list.add(4);
        service.removeBatchByIds(list);
        System.out.println("service.list() = " + service.list());
        HashMap<String, Object> map = new HashMap<>();
        map.put("id", 5);
        map.put("name", "Billie");
        service.removeByMap(map);
        System.out.println("service.list() = " + service.list());
    }


    @Test
    void condition() {
//        QueryWrapper<User> qw = new QueryWrapper<>();
//        qw.select("max(age) as max,min(age) as min");
//        List<Map<String, Object>> res = userMapper.selectMaps(qw);
//        System.out.println(res.get(0));
//        System.out.println(Integer.valueOf(res.get(0).get("max").toString()));
//        System.out.println(Integer.valueOf(res.get(0).get("min").toString()));


        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        String name = "名称";
        Integer minAge = 10, maxAge = 1500;
        /**
         * 如果名字不为空，会按照名称进行查询
         * 如果最小年龄不为空，同时也会将这个条件加进去
         * 如果最大年龄不会空，也会将这个条件加进去
         */
        queryWrapper.eq(name != null, "name", name);
        queryWrapper.ge(minAge != null, "age", minAge);
        queryWrapper.le(maxAge != null, "age", maxAge);
        userMapper.selectList(queryWrapper);
    }

    @Test
    void lambdaQueryWrapperTest() {
        LambdaQueryWrapper<User> lqw = new LambdaQueryWrapper<>();
        lqw.select(User::getName,User::getAge);
        userMapper.selectMaps(lqw).forEach(System.out::println);
    }

    @Test
    public void selectByWrapperPage() {
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        Page<User> page = new Page<>(1,10);
        IPage<User> iPage = userMapper.selectPage(page, queryWrapper);

        System.out.println("总页数: " + iPage.getPages());
        System.out.println("数据总数: " + iPage.getTotal());
        // 返回分页数据
        List<User> userList = iPage.getRecords();
        userList.forEach(System.out::println);

        // 获取分页的其他信息
        System.out.println("当前页号 = " + iPage.getCurrent());
        System.out.println("页大小 = " + iPage.getSize());
    }

    @Test
    public void selectByWrapperPageByAge() {
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        Page<User> page = new Page<>(1,3);
        IPage<User> iPage = userMapper.selectByAge(page,25);
        iPage.getRecords().forEach(System.out::println);

        System.out.println("总页数: " + iPage.getPages());
        System.out.println("数据总数: " + iPage.getTotal());
        // 返回分页数据
        List<User> userList = iPage.getRecords();
        userList.forEach(System.out::println);

        // 获取分页的其他信息
        System.out.println("当前页号 = " + iPage.getCurrent());
        System.out.println("页大小 = " + iPage.getSize());
    }

}