mybatis高级扩展-批量映射优化-mappers标签中使用package批量注册的前提条件

1、建库建表

create database `mybatis-example`;
use `mybatis-example`;
create table emp
(
    empNo   varchar(40),
    empName varchar(100),
    sal int,
    deptno varchar(10)
);
insert into emp values('e001','张三',8000,'d001');
insert into emp values('e002','李四',9000,'d001');
insert into emp values('e003','王五',10000,'d001');
insert into emp values('e004','赵六',11000,'d002');
insert into emp values('e005','田七',12000,'d002');
insert into emp values('e006','周八',13000,'d003');
insert into emp values('e007','吴九',14000,'d004');
insert into emp values('e008','郑十',15000,'d004');
insert into emp values('d8f9b794-95ba-11ee-ab75-84a93ea22bfb','张三丰',16000,'d001');

2、pom.xml

    
        
            org.mybatis
            mybatis
        
 
        
        
            mysql
            mysql-connector-java
        
 
        
        
            org.junit.jupiter
            junit-jupiter-api
        
 
        
            org.projectlombok
            lombok
        
 
        
        
            ch.qos.logback
            logback-classic
        
    

3、Emp.java

package com.atguigu.mybatis.pojo;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Emp {
    private String empNo;
    private Integer sal;
    private String empName;
    private String deptno;
}

4、com/atguigu/mybatis/mappper/EmpMapper.java

package com.atguigu.mybatis.mapper;
import com.atguigu.mybatis.pojo.Emp;
import org.apache.ibatis.annotations.Param;
import java.util.List;
public interface EmpMapper {
    //1.演示where-if标签
    List getEmpList(Emp emp);

    //2、演示set标签
    void updateEmp(Emp emp);

    //3、演示trim标签
    List getEmpList2(Emp emp);

    //4、演示choose/when/otherwise标签
    List getEmpList3(Emp emp);

    //5、演示foreach标签
    List getEmpList4(@Param("empNoList") List empNoList);
}

5、mybatis-config.xml

6、com/atguigu/mybatis/mappper/EmpMapper.xml

    
        select * from emp
        
            
                empNo=#{empNo}
            
            
                and empName=#{empName}
            
            
                and sal < #{sal}
            
            
                and deptno=#{deptno}
            
        
        
    

    
        update emp
        
            
                empName=#{empName},
            
            
                sal=#{sal},
            
            
                deptno=#{deptno}
            
        
        where empNo=#{empNo}
        
    

    
        select * from emp
        
            
                or empNo=#{empNo} or
            
            
                or empName=#{empName} or
            
            
                or sal < #{sal} or
            
            
                or deptno=#{deptno} or
            
        
    

    
        select * from emp where
        
            
                empNo=#{empNo}
            
            
                 empName=#{empName}
            
            
                 sal < #{sal}
            
            
                 deptno=#{deptno}
            
            
                1=1
            
        
    

    
        
        from emp where empNo in
        
            #{employeeNumber}
        
    

    
        select empNo,empName,sal,deptno,'China' as 'address'
    

7、logback.xml

    
    
        
            
            
            [%d{HH:mm:ss.SSS}] [%-5level] [%thread] [%logger] [%msg]%n
            UTF-8
        
    
 
    
    
    
        
        
    
 
    
    

8、MybatisTest.java

package mybatis;
import com.atguigu.mybatis.mapper.EmpMapper;
import com.atguigu.mybatis.pojo.Emp;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
public class MybatisTest {
 
    SqlSessionFactory sqlSessionFactory;
    SqlSession sqlSession;
    EmpMapper empMapper;
 
    @BeforeEach
    public void setup() throws IOException {
        // 获取资源流，读取"mybatis-config.xml"文件
        InputStream inputStream = Resources.getResourceAsStream("mybatis-config.xml");
        // 使用资源流创建SqlSessionFactory
        sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        // 使用SqlSessionFactory打开一个Session
        sqlSession = sqlSessionFactory.openSession();
        //基于Mapper接口编程
        empMapper=sqlSession.getMapper(EmpMapper.class);
    }
 
    // 在每个测试用例之后执行的清理方法
    @AfterEach
    public void teardown() {
        sqlSession.commit();  // 提交事务
        sqlSession.close();  // 关闭SqlSession
    }
 
    @Test
    public void selectWhereIFTest() {
        /**
         * 1、所有条件都不满足
         */
        Emp emp = new Emp();
        empMapper.getEmpList(emp).forEach(System.out::println);//select * from emp
        //Emp(empNo=e001, sal=8000, empName=张三, deptno=d001)
        //Emp(empNo=e002, sal=9000, empName=李四, deptno=d001)
        //Emp(empNo=e003, sal=10000, empName=王五, deptno=d001)
        //Emp(empNo=e004, sal=11000, empName=赵六, deptno=d002)
        //Emp(empNo=e005, sal=12000, empName=田七, deptno=d002)
        //Emp(empNo=e006, sal=13000, empName=周八, deptno=d003)
        //Emp(empNo=e007, sal=14000, empName=吴九, deptno=d004)
        //Emp(empNo=e008, sal=15000, empName=郑十, deptno=d004)
        //Emp(empNo=d8f9b794-95ba-11ee-ab75-84a93ea22bfb, sal=16000, empName=张三丰, deptno=d001)
 
        /**
         * 2、一个条件满足
         */
        Emp emp1 = new Emp();
        emp1.setEmpNo("e002");
        empMapper.getEmpList(emp1).forEach(System.out::println);//select * from emp WHERE empNo=?
        //Emp(empNo=e002, sal=9000, empName=李四, deptno=d001)
 
        Emp emp2 = new Emp();
        emp2.setSal(11000);
        empMapper.getEmpList(emp2).forEach(System.out::println);//select * from emp WHERE sal < ?
        //Emp(empNo=e001, sal=8000, empName=张三, deptno=d001)
        //Emp(empNo=e002, sal=9000, empName=李四, deptno=d001)
        //Emp(empNo=e003, sal=10000, empName=王五, deptno=d001)
 
        Emp emp3 = new Emp();
        emp3.setEmpName("张三丰");
        empMapper.getEmpList(emp3).forEach(System.out::println);//select * from emp WHERE empName=?
        //Emp(empNo=d8f9b794-95ba-11ee-ab75-84a93ea22bfb, sal=16000, empName=张三丰, deptno=d001)
 
        Emp emp4 = new Emp();
        emp4.setDeptno("d001");
        empMapper.getEmpList(emp4).forEach(System.out::println);//select * from emp WHERE deptno=?
        //Emp(empNo=e001, sal=8000, empName=张三, deptno=d001)
        //Emp(empNo=e002, sal=9000, empName=李四, deptno=d001)
        //Emp(empNo=e003, sal=10000, empName=王五, deptno=d001)
        //Emp(empNo=d8f9b794-95ba-11ee-ab75-84a93ea22bfb, sal=16000, empName=张三丰, deptno=d001)
 
        /**
         * 2、两个条件满足
         */
        Emp emp5 = new Emp();
        emp5.setEmpNo("e002");
        emp5.setSal(11000);
        empMapper.getEmpList(emp5).forEach(System.out::println);//select * from emp WHERE empNo=? and sal