java.lang.Exception: CID为空，不能连接数据库！
org.apache.jsp.blog.showArticle_jsp._jspService(showArticle_jsp.java:106)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:332)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:672)
org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:463)
org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:398)
org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:301)
teacherclub.blog.Show.doGet(Show.java:58)
javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
teacherclub.util.EncodingFilter.doFilter(EncodingFilter.java:29)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
org.apache.catalina.valves.FastCommonAccessLogValve.invoke(FastCommonAccessLogValve.java:495)
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
java.lang.Thread.run(Thread.java:595)