4.使用工具类和模板

1.创建模板，mapper文件模板和mybatis主配置文件模板

创建模板的步骤 image.png
image.png
点击new 有模板内容 image.png
工具类

package com.zwx.utils;

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

public class MybatisUtil {
    private static  SqlSessionFactory sqlSessionFactory = null;

    static {
        String config = "mybatiszhu.xml";
        try {
            InputStream inputStream = Resources.getResourceAsStream(config);
             sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    //创建方法获取sqlsession对象
    public  static SqlSession getSqlSession(){
        SqlSession sqlSession = null;
        if (sqlSessionFactory !=null){
            sqlSession=sqlSessionFactory.openSession();
        }
        return sqlSession;
    }


}

测试类

public class Mytest {
    @Test
    public void testSelectById(){
        SqlSession sqlSession = MybatisUtil.getSqlSession();
        String sqlId ="com.zwx.dao.StudentDao"+"."+"selectById";
       Student student = sqlSession.selectOne(sqlId,1002);
        System.out.println(student);
        sqlSession.close();




    }
}