The resource did not process correctly

java.lang.NullPointerException: Cannot invoke "com.zfqjava.service.core.Category.getId()" because "c" is null
	at com.zfqjava.web.website.article.ArticlePath.getArticleListPath(ArticlePath.java:141)
	at com.zfqjava.web.website.article.ArticlePath.getArticleListPath(ArticlePath.java:138)
	at com.zfqjava.web.website.article.ArticlePath.findStaticPage(ArticlePath.java:372)
	at com.zfqjava.web.website.page.StaticPageFilter.doFilter(StaticPageFilter.java:80)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at com.zfqjava.web.website.core.VisitFilter.doFilter(VisitFilter.java:207)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at com.zfqjava.web.RequestFilter.doFilterImpl(RequestFilter.java:567)
	at com.zfqjava.web.RequestFilter.doFilter(RequestFilter.java:125)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
	at com.zfqjava.siteapp.SiteAppFilter.doFilterImpl(SiteAppFilter.java:82)
	at com.zfqjava.siteapp.SiteAppFilter.doFilter(SiteAppFilter.java:56)
	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:202)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:666)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
	at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:747)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
	at org.apache.tomcat.util.net.Nio2Endpoint$SocketProcessor.doRun(Nio2Endpoint.java:1674)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	at org.apache.tomcat.util.net.AbstractEndpoint.processSocket(AbstractEndpoint.java:1104)
	at org.apache.tomcat.util.net.Nio2Endpoint.setSocketOptions(Nio2Endpoint.java:335)
	at org.apache.tomcat.util.net.Nio2Endpoint$Nio2Acceptor.completed(Nio2Endpoint.java:436)
	at org.apache.tomcat.util.net.Nio2Endpoint$Nio2Acceptor.completed(Nio2Endpoint.java:391)
	at java.base/sun.nio.ch.Invoker.invokeUnchecked(Invoker.java:129)
	at java.base/sun.nio.ch.Invoker$2.run(Invoker.java:221)
	at java.base/sun.nio.ch.AsynchronousChannelGroupImpl$1.run(AsynchronousChannelGroupImpl.java:113)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.base/java.lang.Thread.run(Thread.java:833)