SpringBoot2 黑马B站版 -08 SpringBoot的SSMP整合案例 - 分页与条件查询

• 添加分页代码
• 配置拦截器，否则上面的分页会查询所有数据
• 接受分页查询数据并展示
• ------------------------------
• 添加按条件查询代码

package com.abc;

import com.abc.dao.StudentDao;
import com.abc.entity.Student;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.List;

@SpringBootTest
class LearnApplicationTests {


    @Autowired
    private StudentDao dao;





    @Test
    void contextLoads() {

        System.out.println("------------------------------------");
        //分页
        IPage page=new Page(1,5);//第几页，每页数据量
        dao.selectPage(page, null);

        System.out.println("------------------------------------");
    }

}

此拦截器是个普通的Bean类，之所以可以被扫描识别是因为他有@Configuration注解

package com.abc.config;

import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import lombok.Data;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;




@Configuration//配置类
public class MPConfig {
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor(){
        //创建拦截器
        MybatisPlusInterceptor interceptor=new MybatisPlusInterceptor();
        //配置拦截器
        //这只是其中一个拦截器，如有其他拦截器的话，直接在后面行加上即可。
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor());
//        interceptor.addInnerInterceptor(new AAA());
//        interceptor.addInnerInterceptor(new BBB());


        return interceptor;
    }
}

package com.abc;

import com.abc.dao.StudentDao;
import com.abc.entity.Student;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.List;

@SpringBootTest
class LearnApplicationTests {


    @Autowired
    private StudentDao dao;





    @Test
    void contextLoads() {

        System.out.println("------------------------------------");


        //分页
        IPage page=new Page(1,5);//第几页，每页数据量
        IPage iPage= dao.selectPage(page, null);
        System.out.println(iPage.getPages());
        System.out.println(iPage.getCurrent());
        System.out.println(iPage.getRecords());
        System.out.println(iPage.getSize());
        System.out.println(iPage.getTotal());






        System.out.println("------------------------------------");
    }

}

package com.abc;

import com.abc.dao.StudentDao;
import com.abc.entity.Student;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.awt.print.Book;
import java.util.List;

@SpringBootTest
class LearnApplicationTests {


    @Autowired
    private StudentDao dao;





    @Test
    void contextLoads() {

        System.out.println("=====================================");

        QueryWrapper qw=new QueryWrapper<>();
        //添加条件
        qw.like("name", "雷电将军");
        dao.selectList(qw);

        System.out.println("------------------------------------");

        LambdaQueryWrapper lqw=new LambdaQueryWrapper<>();
        //无判断条件
        lqw.like(Student::getName,"电");
        //有判断条件
        lqw.like(1==1,Student::getName,"电");
        dao.selectList(lqw);

        System.out.println("=====================================");
    }

}