The at org. Apache. Catalina. Valves. ErrorReportValve. Invoke (ErrorReportValve. Java: 92)
The at org. Apache. Catalina. Valves. AbstractAccessLogValve. Invoke (AbstractAccessLogValve. Java: 690)
The at org. Apache. Catalina. Core. StandardEngineValve. Invoke (StandardEngineValve. Java: 78)
At org. Apache. Catalina. Connector. CoyoteAdapter. Service (343) CoyoteAdapter. Java:
At org. Apache. Coyote. Http11. Http11Processor. Service (374) Http11Processor. Java:
The at org. Apache. Coyote. AbstractProcessorLight. Process (AbstractProcessorLight. Java: 65)
The at org. Apache. Coyote. AbstractProtocol $ConnectionHandler. Process (AbstractProtocol. Java: 880)
At org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun NioEndpoint. Java: (1601)
The at org.apache.tomcat.util.net.SocketProcessorBase.run (SocketProcessorBase. Java: 49)
The at Java. Util. Concurrent. ThreadPoolExecutor. RunWorker (ThreadPoolExecutor. Java: 1149)
The at Java. Util. Concurrent. ThreadPoolExecutor $Worker. The run (ThreadPoolExecutor. Java: 624)
At org, apache tomcat. Util. Threads. TaskThread $WrappingRunnable. Run (61) TaskThread. Java:
The at Java. Lang. Thread. The run (Thread. Java: 748)
23 - Nov - 2020 23:38:01. 071 serious [HTTP - nio - 8080 - exec - 4] org. Apache. Catalina. Core. StandardWrapperValve. Invoke the path for [/wzu] context, the servlet/indexAction servlet. Service () throw exceptions
Java. Lang. NullPointerException
The at campsg. Qunawan. Action. IndexAction. DoGet (IndexAction. Java: 63)
The at javax.mail. Servlet. HTTP. HttpServlet. Service (HttpServlet. Java: 626)
The at javax.mail. Servlet. HTTP. HttpServlet. Service (HttpServlet. Java: 733)
The at campsg. Qunawan. Proxy. DelegatingServletProxy. Service (DelegatingServletProxy. Java: 26)
The at org. Apache. Catalina. Core. ApplicationFilterChain. InternalDoFilter (ApplicationFilterChain. Java: 231)
The at org. Apache. Catalina. Core. ApplicationFilterChain. DoFilter (ApplicationFilterChain. Java: 166)
At org, apache tomcat, websocket server WsFilter. DoFilter (53) WsFilter. Java:
The at org. Apache. Catalina. Core. ApplicationFilterChain. InternalDoFilter (ApplicationFilterChain. Java: 193)
The at org. Apache. Catalina. Core. ApplicationFilterChain. DoFilter (ApplicationFilterChain. Java: 166)
The at campsg. Qunawan. Filter. UserFilter. DoFilter (UserFilter. Java: 54)
The at org. Apache. Catalina. Core. ApplicationFilterChain. InternalDoFilter (ApplicationFilterChain. Java: 193)
The at org. Apache. Catalina. Core. ApplicationFilterChain. DoFilter (ApplicationFilterChain. Java: 166)
The at campsg. Qunawan. Filter. SetCharacterEncodingFilter. DoFilter (SetCharacterEncodingFilter. Java: 36)
The at org. Apache. Catalina. Core. ApplicationFilterChain. InternalDoFilter (ApplicationFilterChain. Java: 193)
The at org. Apache. Catalina. Core. ApplicationFilterChain. DoFilter (ApplicationFilterChain. Java: 166)
The at org. Apache. Catalina. Core. StandardWrapperValve. Invoke (StandardWrapperValve. Java: 202)
The at org. Apache. Catalina. Core. StandardContextValve. Invoke (StandardContextValve. Java: 97)
The at org. Apache. Catalina. The authenticator. AuthenticatorBase. Invoke (AuthenticatorBase. Java: 542)
The at org. Apache. Catalina. Core. StandardHostValve. Invoke (StandardHostValve. Java: 143)
The at org. Apache. Catalina. Valves. ErrorReportValve. Invoke (ErrorReportValve. Java: 92)
The at org. Apache. Catalina. Valves. AbstractAccessLogValve. Invoke (AbstractAccessLogValve. Java: 690)
The at org. Apache. Catalina. Core. StandardEngineValve. Invoke (StandardEngineValve. Java: 78)
At org. Apache. Catalina. Connector. CoyoteAdapter. Service (343) CoyoteAdapter. Java:
At org. Apache. Coyote. Http11. Http11Processor. Service (374) Http11Processor. Java:
The at org. Apache. Coyote. AbstractProcessorLight. Process (AbstractProcessorLight. Java: 65)
The at org. Apache. Coyote. AbstractProtocol $ConnectionHandler. Process (AbstractProtocol. Java: 880)
At org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun NioEndpoint. Java: (1601)
The at org.apache.tomcat.util.net.SocketProcessorBase.run (SocketProcessorBase. Java: 49)
The at Java. Util. Concurrent. ThreadPoolExecutor. RunWorker (ThreadPoolExecutor. Java: 1149)
The at Java. Util. Concurrent. ThreadPoolExecutor $Worker. The run (ThreadPoolExecutor. Java: 624)
At org, apache tomcat. Util. Threads. TaskThread $WrappingRunnable. Run (61) TaskThread. Java:
The at Java. Lang. Thread. The run (Thread. Java: 748)

CodePudding user response:

Java. Lang. NullPointerException
The at campsg. Qunawan. Action. IndexAction. DoGet (IndexAction. Java: 63)

Compared with other abnormalities, NullPointerException is easy to solve the abnormal
Find campsg. Qunawan. Action. IndexAction 63 rows, there is a variable's value is null, but in this line of attempts to access the variable properties or methods of what,