由于重复提交response，所以出现这样的错误！
异常信息：Cannot forward after response has been committed
出错原因：在同一个Servlet/JSP中出现了两个request.getRequestDispatcher().forward()语句
解决办法：在forward()语句后添加return()语句。
【上篇】[mircroftt][sqlserver 2000 driver for jdbc][sqlserver]对象名
【下篇】java.sql.SQLException: Io 异常: Connection refused(DESCRIPTION=(TMP=)(VSNNUM=169869568)(ERR=12519)(ERROR_STACK=(ERROR=(CODE=12519)
【下篇】java.sql.SQLException: Io 异常: Connection refused(DESCRIPTION=(TMP=)(VSNNUM=169869568)(ERR=12519)(ERROR_STACK=(ERROR=(CODE=12519)