8、mybatis之增刪改查

1、EmployeeMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!--指定爲接口的全類名-->
<mapper namespace="com.mi.dao.EmployeeMapper">
    <!--id 爲接口的方法名-->
    <select id="getEmployeeById" resultType="com.mi.pojo.Employee">
        select * from employee where id = #{id}
    </select>

    <insert id="addEmp" parameterType="com.mi.pojo.Employee">
        insert into employee (last_name,gender) values (#{lastName},#{gender})
    </insert>
    
    <delete id="deleteEmp">
        delete from employee where id = #{id}
    </delete>

    <update id="updateEmp" >
        update employee set last_name = #{lastName},gender = #{gender} where id = #{id}
    </update>
</mapper>

2、測試增刪改查

package com.mi.test;

import com.mi.dao.EmployeeMapper;
import com.mi.pojo.Employee;
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.Test;

import java.io.IOException;
import java.io.InputStream;

public class TestMybatis {

    public SqlSessionFactory getSqlSessionFactory() throws IOException {
        String resource  = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        return new SqlSessionFactoryBuilder().build(inputStream);
    }

    @Test
    public void testGet() throws IOException {
        //1、獲取SqlSessionFactory對象
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        //2、獲取Sqlsesion對象
        SqlSession sqlSession = sqlSessionFactory.openSession();

        try {
            //3、獲取接口的實現類對象
            //會爲接口自動創建一個代理對象，代理對象去執行增刪改查方法
            EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class);
            Employee employee = mapper.getEmployeeById(3);
            System.out.println(employee);
        }finally {
            sqlSession.close();
        }
    }

    @Test
    public void testAdd() throws IOException {
        //1、獲取SqlSessionFactory對象
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        //2、獲取Sqlsesion對象
        SqlSession sqlSession = sqlSessionFactory.openSession();

        try {
            //3、獲取接口的實現類對象
            //會爲接口自動創建一個代理對象，代理對象去執行增刪改查方法
            EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class);
            Integer employee = mapper.addEmp(new Employee(null,"jerry","1"));
            sqlSession.commit();
            System.out.println(employee);
        }finally {
            sqlSession.close();
        }
    }

    @Test
    public void testDel() throws IOException {
        //1、獲取SqlSessionFactory對象
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        //2、獲取Sqlsesion對象
        SqlSession sqlSession = sqlSessionFactory.openSession();

        try {
            //3、獲取接口的實現類對象
            //會爲接口自動創建一個代理對象，代理對象去執行增刪改查方法
            EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class);
            Integer employee = mapper.deleteEmp(1);
            sqlSession.commit();
            System.out.println(employee);
        }finally {
            sqlSession.close();
        }
    }

    @Test
    public void testUpdate() throws IOException {
        //1、獲取SqlSessionFactory對象
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        //2、獲取Sqlsesion對象
        SqlSession sqlSession = sqlSessionFactory.openSession();

        try {
            //3、獲取接口的實現類對象
            //會爲接口自動創建一個代理對象，代理對象去執行增刪改查方法
            EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class);
            Integer employee = mapper.updateEmp(new Employee(3,"jerry","0"));
            sqlSession.commit();
            System.out.println(employee);
        }finally {
            sqlSession.close();
        }
    }

}