网站出现错误

java.lang.NullPointerException at net.njd.web.controller.NewsController.associationDetailShow(NewsController.java:288) at sun.reflect.GeneratedMethodAccessor55.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:55) at net.njd.web.interceptor.WebFrontAttrInterceptor.intercept(WebFrontAttrInterceptor.java:19) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at com.jfinal.ext.interceptor.ExceptionInterceptor.intercept(ExceptionInterceptor.java:53) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at net.njd.web.interceptor.BaseAttrInterceptor.intercept(BaseAttrInterceptor.java:22) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at net.njd.web.interceptor.LogAttrInterceptor.intercept(LogAttrInterceptor.java:42) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at com.jfinal.core.ActionHandler.handle(ActionHandler.java:73) at com.jfinal.plugin.druid.DruidStatViewHandler.handle(DruidStatViewHandler.java:75) at com.jfinal.core.JFinalFilter.doFilter(JFinalFilter.java:72) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at net.njd.web.filter.CookieFilter.doFilter(CookieFilter.java:48) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at net.njd.web.filter.XSSFilter.doFilter(XSSFilter.java:71) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:470) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:615) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11NioProcessor.process(Http11NioProcessor.java:891) at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:760) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:2290) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745)