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Question

最后我点vote.gif运行的结果是
 The server encountered an internal error (Internal Server Error) that prevented it from fulfilling this request.exception java.lang.NullPointerException
at org.apache.jsp.dovote$jsp._jspService(dovote$jsp.java:104)
at org.apache.jasper.runtime.HttpJspBase.service(Unknown Source)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(Unknown Source)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(Unknown Source)
at org.apache.jasper.servlet.JspServlet.service(Unknown Source)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Unknown Source)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(Unknown Source)
at org.apache.catalina.core.StandardWrapperValve.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invoke(Unknown Source)
at org.apache.catalina.core.ContainerBase.invoke(Unknown Source)
at org.apache.catalina.core.StandardContextValve.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invoke(Unknown Source)
at org.apache.catalina.core.ContainerBase.invoke(Unknown Source)
at org.apache.catalina.core.StandardContext.invoke(Unknown Source)
at org.apache.catalina.core.StandardHostValve.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.valves.ErrorReportValve.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.valves.AccessLogValve.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invoke(Unknown Source)
at org.apache.catalina.core.ContainerBase.invoke(Unknown Source)
at org.apache.catalina.core.StandardEngineValve.invoke(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invokeNext(Unknown Source)
at org.apache.catalina.core.StandardPipeline.invoke(Unknown Source)
at org.apache.catalina.core.ContainerBase.invoke(Unknown Source)
at org.apache.catalina.connector.http.HttpProcessor.process(Unknown Source)
at org.apache.catalina.connector.http.HttpProcessor.run(Unknown Source)
at java.lang.Thread.run(Thread.java:484)