封装mybatis工具类 减少factory实例化过程，简化代码，提高效率！

封装mybatis工具类 减少factory实例化过程，简化代码，提高效率！

package com.jkbd.util;

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

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

public class MyBatisUtil {
    //factory实例化的过程是一个比较耗费性能的过程.
    //保证有且只有一个factory
    private static SqlSessionFactory factory;
    private static ThreadLocal tl = new ThreadLocal<>();
    static{
        try {
            InputStream is = Resources.getResourceAsStream("mybatis.xml");
            factory = new SqlSessionFactoryBuilder().build(is);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    /**
     * 获取SqlSession的方法
     */
    public static SqlSession getSession(){
        SqlSession session = tl.get();
        if(session==null){
            tl.set(factory.openSession());
        }
        return tl.get();
    }

    public static void closeSession(){
        SqlSession session = tl.get();
        if(session!=null){
            session.close();
        }
        tl.set(null);
    }
}

最开始是由Spring框架提出的.整合Hibernate框架是使用的是OpenSessionInView

package com.jkbd.filter;

import java.io.IOException;

import java.io.InputStream;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;

import com.jkbd.util.MyBatisUtil;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;



/**
 * 最开始是由Spring框架提出的.整合Hibernate框架是使用的是OpenSessionInView
 *
 *
 * @author Administrator
 *
 */
@WebFilter("/*")
public class OpenSessionInView implements Filter{

    @Override
    public void init(FilterConfig filterconfig) throws ServletException {
        // TODO Auto-generated method stub

    }

    @Override
    public void doFilter(ServletRequest servletrequest, ServletResponse servletresponse, FilterChain filterchain)
            throws IOException, ServletException {
//		InputStream is = Resources.getResourceAsStream("mybatis.xml");
//		SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
//		SqlSession session = factory.openSession();
        SqlSession session = MyBatisUtil.getSession();
        try {
            filterchain.doFilter(servletrequest, servletresponse);
            session.commit();
        } catch (Exception e) {
            session.rollback();
            e.printStackTrace();
        }finally{
            MyBatisUtil.closeSession();
        }
//		session.commit();
//		session.close();
    }

    @Override

    public void destroy() {
        // TODO Auto-generated method stub

    }

}

实现类代码量大大减少

package com.jkbd.service.impl;

import com.jkbd.mapper.LogMapper;
import com.jkbd.pojo.Log;
import com.jkbd.service.LogService;
import com.jkbd.util.MyBatisUtil;
import org.apache.ibatis.session.SqlSession;

public class LogServiceImpl implements LogService {

    @Override
    public int ins(Log log) {
        SqlSession session = MyBatisUtil.getSession();
   LogMapper mapper = session.getMapper(LogMapper.class);
        return mapper.ins(log);
    }
}