ThreadLocal + Filter 处理事务

短命女 2022-07-15 03:59 169阅读 0赞

![070808249216296.png][]

package me.gac.web.filter;  
  
  
import java.io.IOException;  
import java.sql.Connection;  
import java.sql.SQLException;  
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.http.HttpServletRequest;  
import javax.servlet.http.HttpServletResponse;  
import me.gacl.util.JdbcUtils;  
  
  
/\*\*  
\* @ClassName: TransactionFilter  
\* @Description:ThreadLocal + Filter 统一处理数据库事务  
\* @author: 孤傲苍狼  
\* @date: 2014-10-6 下午11:36:58  
\*  
\*/   
public class TransactionFilter implements Filter \{  
  
  
    @Override  
    public void init(FilterConfig filterConfig) throws ServletException \{  
  
  
    \}  
  
  
    @Override  
    public void doFilter(ServletRequest request, ServletResponse response,  
            FilterChain chain) throws IOException, ServletException \{  
  
  
        Connection connection = null;  
        try \{  
            //1、获取数据库连接对象Connection  
            connection = JdbcUtils.getConnection();  
            //2、开启事务  
            connection.setAutoCommit(false);  
            //3、利用ThreadLocal把获取数据库连接对象Connection和当前线程绑定  
            ConnectionContext.getInstance().bind(connection);  
            //4、把请求转发给目标Servlet  
            chain.doFilter(request, response);  
            //5、提交事务  
            connection.commit();  
        \} catch (Exception e) \{  
            e.printStackTrace();  
            //6、回滚事务  
            try \{  
                connection.rollback();  
            \} catch (SQLException e1) \{  
                e1.printStackTrace();  
            \}  
            HttpServletRequest req = (HttpServletRequest) request;  
            HttpServletResponse res = (HttpServletResponse) response;  
            //req.setAttribute("errMsg", e.getMessage());  
            //req.getRequestDispatcher("/error.jsp").forward(req, res);  
            //出现异常之后跳转到错误页面  
            res.sendRedirect(req.getContextPath()+"/error.jsp");  
        \}finally\{  
            //7、解除绑定  
            ConnectionContext.getInstance().remove();  
            //8、关闭数据库连接  
            try \{  
                connection.close();  
            \} catch (SQLException e) \{  
                e.printStackTrace();  
            \}  
        \}  
    \}  
  
  
    @Override  
    public void destroy() \{  
  
  
    \}  
\}

[070808249216296.png]: /images/20220715/74283322dab74ad19d6bb38c59edb921.png