MyBatis入门02 实现CRUD

在上一篇博客MyBatis入门01的基础：

1、定义sql映射xml文件：

<?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="com.atguigu.day03_mybaits.test2.userMapper">
    <!-- 
        CRUD操作

     -->
     <insert id="addUser" parameterType="User">
        insert into users(name, age) values(#{name}, #{age})
     </insert>

     <delete id="deleteUser" parameterType="int">
        delete from users where id=#{id}
     </delete>

     <update id="updateUser" parameterType="User">
        update users set name=#{name},age=#{age} where id=#{id}
     </update>

     <select id="getUser" parameterType="int" resultType="User">
        select * from users where id=#{id}
     </select>

     <select id="getAllUsers" resultType="User">
        select * from users
     </select>
</mapper>

2). 在config.xml中注册这个映射文件：

<mapper resource=" com/atguigu/ibatis/bean/userMapper.xml"/>

3编写MybatisUtil工具类：

package com.atguigu.day03_mybaits.util;

import java.io.InputStream;

import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import com.atguigu.day03_mybaits.test1.Test;

public class MybatisUtils {

    public static SqlSessionFactory getFactory() {
        String resource = "conf.xml";
        InputStream is = Test.class.getClassLoader().getResourceAsStream(
                resource);

        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);

        return factory;
    }
}

4、编写MyBatis测试类：

package com.atguigu.day03_mybaits.test2;

import java.util.List;

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.junit.Test;

import com.atguigu.day03_mybaits.bean.User;
import com.atguigu.day03_mybaits.test3.UserMapper;
import com.atguigu.day03_mybaits.util.MybatisUtils;
/*
 * 测试: CRUD操作的XML的实现
 */
public class Test2 {

    @Test
    public void testAdd() {
        SqlSessionFactory factory = MybatisUtils.getFactory();
        //默认是手动提交的
        SqlSession session = factory.openSession();

        String statement = "com.atguigu.day03_mybaits.test2.userMapper.addUser";
        int insert = session.insert(statement , new User(-1, "KK", 23));
        //提交
        session.commit();

        session.close();

        System.out.println(insert);
    }

    @Test
    public void testUpate() {
        SqlSessionFactory factory = MybatisUtils.getFactory();
        //默认是手动提交的
        SqlSession session = factory.openSession(true);

        String statement = "com.atguigu.day03_mybaits.test2.userMapper.updateUser";

        int update = session.update(statement, new User(4, "KK444", 25));

        session.close();
        System.out.println(update);
    }

    @Test
    public void testDelete() {
        SqlSessionFactory factory = MybatisUtils.getFactory();
        //默认是手动提交的
        SqlSession session = factory.openSession(true);

        String statement = "com.atguigu.day03_mybaits.test2.userMapper.deleteUser";

        int delete = session.delete(statement, 4);

        session.close();
        System.out.println(delete);
    }

    @Test
    public void testGetUser() {
        SqlSessionFactory factory = MybatisUtils.getFactory();
        //默认是手动提交的
        SqlSession session = factory.openSession(true);

        String statement = "com.atguigu.day03_mybaits.test2.userMapper.getUser";

        User user = session.selectOne(statement, 1);

        session.close();
        System.out.println(user);
    }

    @Test
    public void testGetAll() {
        SqlSessionFactory factory = MybatisUtils.getFactory();
        //默认是手动提交的
        SqlSession session = factory.openSession(true);

        String statement = "com.atguigu.day03_mybaits.test2.userMapper.getAllUsers";

        List<User> list = session.selectList(statement);

        session.close();
        System.out.println(list);
    }


    @Test
    public void testAdd2() {
        SqlSessionFactory factory = MybatisUtils.getFactory();
        //默认是手动提交的
        SqlSession session = factory.openSession(true);

        UserMapper mapper = session.getMapper(UserMapper.class);
        int add = mapper.add(new User(-1, "SS", 45));
        System.out.println(add);

        session.close();
    }

}