package com.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;

/**

 * @author: XDZY

 * @date: 2018/8/8 14:50

 * @description: SessionFactory工厂

 */

public class SqlSessionFactoryUtils {

    private final static Class<SqlSessionFactoryUtils> LOCK = SqlSessionFactoryUtils.class;

    private static SqlSessionFactory sqlSessionFactory = null;

    private SqlSessionFactoryUtils() {

    }

    public static SqlSessionFactory getSqlSessionFactory() {

        synchronized (LOCK) {

            if (sqlSessionFactory != null) {

                return sqlSessionFactory;

            }

            String resource = "com/mybatis-config.xml";

            InputStream inputStream;

            try {

                inputStream = Resources.getResourceAsStream(resource);

                sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);

            } catch (IOException e) {

                e.printStackTrace();

                return null;

            }

            return sqlSessionFactory;

        }

    }

    public static SqlSession openSqlSession() {

        if (sqlSessionFactory == null) {

            getSqlSessionFactory();

        }

        return sqlSessionFactory.openSession();

    }

}

package com.main;

import com.mapper.RoleMapper;

import com.pojo.Role;

import com.utils.SqlSessionFactoryUtils;

import org.apache.ibatis.session.SqlSession;

/**

 * @author: XDZY

 * @date: 2018/8/8 15:12

 * @description: 运行入口

 */

public class TestMain {

    public static void main(String[] args) {

        SqlSession sqlSession = null;

        try {

            sqlSession = SqlSessionFactoryUtils.openSqlSession();

            RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);

            Role role = roleMapper.getRole(1L);

            System.out.println(role.getRoleName());

        } finally {

            if (sqlSession != null) {

                sqlSession.close();

            }

        }

    }

}