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错误：javax.servlet.ServletException: java.lang.NullPointerException
错误码：500
异常：null
exception:javax.servlet.ServletException: java.lang.NullPointerException
cause:java.lang.NullPointerException
message:java.lang.NullPointerException
localizedMessage:java.lang.NullPointerException
stackTrace:javax.servlet.ServletException: java.lang.NullPointerException at org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:535) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:433) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) at javax.servlet.http.HttpServlet.service(HttpServlet.java:656) at javax.servlet.http.HttpServlet.service(HttpServlet.java:765) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.lyt.util.filter.CountDayBrowseFilter.doFilter(CountDayBrowseFilter.java:47) at com.lyt.util.HttpFilter.doFilter(HttpFilter.java:46) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.tuckey.web.filters.urlrewrite.RuleChain.handleRewrite(RuleChain.java:164) at org.tuckey.web.filters.urlrewrite.RuleChain.doRules(RuleChain.java:141) at org.tuckey.web.filters.urlrewrite.UrlRewriter.processRequest(UrlRewriter.java:90) at org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:406) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.lyt.util.filter.UrlRedirectFilter.doFilter(UrlRedirectFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.magtech.filter.UserGroupMapFilter.doFilter(UserGroupMapFilter.java:39) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.magtech.filter.XssFilter.doFilter(XssFilter.java:66) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.lyt.util.web.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:44) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.lyt.util.filter.FrameTaoFilter.doFilter(FrameTaoFilter.java:29) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.lyt.util.filter.JournalIDFilter.doFilter(JournalIDFilter.java:80) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.lyt.util.filter.ReadRequestRefererFilter.doFilter(ReadRequestRefererFilter.java:32) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at com.lyt.util.filter.AuthenticationFilter.doFilter(AuthenticationFilter.java:89) at com.lyt.util.HttpFilter.doFilter(HttpFilter.java:46) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:543) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:769) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:698) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:367) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:639) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:885) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1693) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748) Caused by: java.lang.NullPointerException at java.util.Calendar.setTime(Calendar.java:1770) at java.text.SimpleDateFormat.format(SimpleDateFormat.java:943) at java.text.SimpleDateFormat.format(SimpleDateFormat.java:936) at java.text.DateFormat.format(DateFormat.java:345) at com.wkxt.article.web.action.ArticleDownloadFileAction.execute(ArticleDownloadFileAction.java:594) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) ... 63 more