springboot笔记（三）

编写过滤器

package com.example.demo.config;

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


@Configuration
//配置类这样里面的配置信息可以被读取。
public class MPConfig {
//    拦截器 limt
    @Bean
//    第三方Bean mp的拦截器，当你需要定义多个拦截器时候可以创建
    public MybatisPlusInterceptor mybatisPlusInterceptor(){
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor());
        return interceptor;
    }
}

编写业务层server层

package com.example.demo.service;

import com.baomidou.mybatisplus.core.metadata.IPage;
import com.example.demo.domain.User;

import java.util.List;


//业务层 service
//接口写完了得写实现类
public interface UserService {

    Boolean  save(User user);

    Boolean  updata(User user);

    Boolean  delete(Integer id);
    
    User getById(Integer id);

    List getALL();


    IPage getPage(int currentPage,int pagesize);
}

编写实现了implement

package com.example.demo.impl;

import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.example.demo.dao.UserDao;
import com.example.demo.domain.User;
import com.example.demo.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;


//UserService接口的实现类的实现类
//    implements 实现接口 加上之后可以实现指定泛型的抽象方法
//    @Service用来定义业务层的bean
@Service
public class UserServiceImpl implements UserService {

//    转调数据层需要注入
    @Autowired
    private UserDao userDao;

    @Override
    public Boolean save(User user) {
//        返回值为null 编写查询方法
//        return userDao.insert(user) 中insert是影响行操作设置
        return userDao.insert(user) >0;
    }

    @Override
    public Boolean updata(User user) {
        return userDao.updateById(user) >0;
    }

    @Override
    public Boolean delete(Integer id) {
        return userDao.deleteById(id) >0;
    }

    @Override
    public User getById(Integer id) {
        return userDao.selectById(id);
    }

    @Override
    public List getALL() {
        return userDao.selectList(null);
    }

    @Override
    public IPage getPage(int currentPage,int pagesize) {
        IPage objectIPage = new Page(currentPage,pagesize);
        userDao.selectPage(objectIPage,null);
        return objectIPage;
    }
}

编写测试类

package com.example.demo.service;

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 com.example.demo.domain.User;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;


@SpringBootTest
//测试注解
public class UserServiceTest {


    @Autowired
    private UserService userService;

    @Test
    void contextLoads() {
        System.out.println(userService.getById(1));
    }
    @Test
    void testsave() {
        User user =  new User();
//        mp中使用id的增加策略是雪花算法 如果设置了id自增需要另写配置在application.yml
        user.setUsername("亚索");
        user.setPassword("eeeeee");
        user.setAccount("aaqaqr");
        userService.save(user);
    }
    @Test
    void testupdate(){
        User user =  new User();
//        mp中使用id的增加策略是雪花算法 如果设置了id自增需要另写配置在application.yml
        user.setId(3);
        user.setUsername("吴亦凡");
        user.setPassword("eeeeee");
        user.setAccount("wordbig");
        userService.updata(user);
    }
    @Test
    void testDelete(){
        userService.delete(2);
    }
    @Test
    void testSeletALL(){
        System.out.println(userService.getALL());
    }
    @Test
    void testbGetpage(){
        IPage page = userService.getPage(1,1);
        System.out.println(page.getPages());
        System.out.println(page.getTotal());
        System.out.println(page.getSize());
        System.out.println(page.getCurrent());
        System.out.println(page.getRecords());
    }

}