环境搭建参考上一章,本节内容通过更新userMapper.xml和test测试类实现增删改查
1、userMapper.xml代码
<?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">
<mapper namespace="javastudy.UserMapper">
<select id="selectUser" resultType="javastudy.User">
select * from user where id = #{id}
</select>
<select id="selectAll" resultType="javastudy.User">
select * from user
</select>
<insert id="addUser" parameterType="javastudy.User">
insert into user (userName,userPwd) values (#{userName},#{userPwd})
</insert>
<update id="updateUser" parameterType="javastudy.User">
update user set userName=#{userName},userPwd=#{userPwd} where id=#{id}
</update>
<delete id="deleteUser" parameterType="int">
delete from user where id=#{id}
</delete>
</mapper>
2、mybatis的主配置文件mybatis-config.xml 中需要配置
<mappers>
<mapper resource="javastudy/userMapper.xml"/>
</mappers>
3、user 实体做set和get
4、test测试类代码
package test;
import java.io.IOException;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
import javastudy.User;
import utility.MyBatisUtils;
public class MyTest {
@Test
public void testSelect() throws IOException {
SqlSession session=MyBatisUtils.openSession();
String statement="javastudy.UserMapper.selectUser"; //确定sql语句
User user=session.selectOne(statement,1);//返回一条记录,返回一条对象
System.out.println(user);
session.close();
}
@Test
public void testSelectAll() throws IOException {
SqlSession session=MyBatisUtils.openSession();
String statement="javastudy.UserMapper.selectAll";
List<User> list=session.selectList(statement);
System.out.println(list);
session.close();
}
@Test
public void testInsert() throws IOException {
SqlSession session=MyBatisUtils.openSession();
String statement="javastudy.UserMapper.addUser";
User user=new User();
user.setUserName("zhang");
user.setUserPwd("987654");
session.insert(statement, user);
session.commit();
session.close();
}
@Test
public void testUpdate() throws IOException {
SqlSession session=MyBatisUtils.openSession();
String statement="javastudy.UserMapper.updateUser";
User user=new User();
user.setId(3);
user.setUserName("王3");
user.setUserPwd("00000");
session.update(statement, user);
session.commit();
session.close();
}
@Test
public void testDelete() throws IOException {
SqlSession session=MyBatisUtils.openSession();
String statement="javastudy.UserMapper.deleteUser";
session.delete(statement,3);
session.commit();
session.close();
}
}