Mybatis獲取Sqlsession的工具類

 

package com.jyk.mybatis.util;

import java.io.IOException;
import java.io.Reader;
import java.sql.Connection;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

/*
 * MyBatis工具類
 */
public class MyBatisUtil {

    private static ThreadLocal<SqlSession> threadLocal = new
            ThreadLocal<SqlSession>();
    private static SqlSessionFactory sqlSessionFactory;
    
    //靜態塊加載src目錄下的mybatis配置文件
    static{
        try {
            Reader reader = Resources.getResourceAsReader("mybatis.xml");
            sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    /*
     * 禁止外界通過new方法創建
     */
    private MyBatisUtil(){}
    
    /*
     * 獲取sqlsession
     */
    public static SqlSession getSqlSession()
    {
        //從當前線程中獲取sqlSession對象
        SqlSession sqlSession = threadLocal.get();
        
        //判斷SqlSession對象是否為空
        if(sqlSession==null)
        {
            //在SqlSessionFactory對象非空的情況下，獲取SqlSession對象
            sqlSession = sqlSessionFactory.openSession();
            //將SqlSession對象與當前線程綁定在一起
            threadLocal.set(sqlSession);
        }
        
        return sqlSession;
    }
    
    /*
     * 關閉sqlsession與當前線程分開
     */
    public static void closeSqlSession()
    {
        //從當前線程中獲取SqlSession對象
        SqlSession sqlSession = threadLocal.get();
        
        if(sqlSession != null)
        {
            //關閉SqlSession對象
            sqlSession.close();
            //分開當前線程與SqlSession對象的關系，目的是盡早進行垃圾回收
            threadLocal.remove();
        }        
    }
    
    /*
     * 測試方法
     */
    public static void main(String[] args) {
        Connection conn = MyBatisUtil.getSqlSession().getConnection();
        if(conn==null)
        {
            System.out.println("連接為空");
        }
        else
        {
            System.out.println("連接不為空");
        }
    }
}