thymeleaf Error: An error happened during template parsing Cannot render error page for request

By looking at the front-end html code, there is a syntax error
Although I have commented out the error code
but the use of <! –> can only keep the browser from displaying it, but it can’t keep the thymeleaf template engine from parsing it.
I should have used the thymeleaf comment syntax <! –/* */–> to comment it out

The error message is as follows.

2022-02-23 09:42:12.418 ERROR 14216 --- [nio-8080-exec-1] org.thymeleaf.TemplateEngine             : [THYMELEAF][http-nio-8080-exec-1] Exception processing template "indexPage": An error happened during template parsing (template: "class path resource [templates/indexPage.html]")

org.thymeleaf.exceptions.TemplateInputException: An error happened during template parsing (template: "class path resource [templates/indexPage.html]")
	at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parse(AbstractMarkupTemplateParser.java:241) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parseStandalone(AbstractMarkupTemplateParser.java:100) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.engine.TemplateManager.parseAndProcess(TemplateManager.java:666) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1098) [thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1072) [thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.spring5.view.ThymeleafView.renderFragment(ThymeleafView.java:366) [thymeleaf-spring5-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.spring5.view.ThymeleafView.render(ThymeleafView.java:190) [thymeleaf-spring5-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1401) [spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1145) [spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1084) [spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) [spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) [spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) [spring-webmvc-5.3.15.jar:5.3.15]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:655) [tomcat-embed-core-9.0.56.jar:4.0.FR]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) [spring-webmvc-5.3.15.jar:5.3.15]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) [tomcat-embed-core-9.0.56.jar:4.0.FR]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) [tomcat-embed-websocket-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) [spring-web-5.3.15.jar:5.3.15]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.15.jar:5.3.15]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) [spring-web-5.3.15.jar:5.3.15]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.15.jar:5.3.15]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-5.3.15.jar:5.3.15]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.15.jar:5.3.15]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:540) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:382) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:895) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1732) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131]
Caused by: org.attoparser.ParseException: Exception evaluating SpringEL expression: "session.getAttribute("loginuser").username" (template: "indexPage" - line 375, col 31)
	at org.attoparser.MarkupParser.parseDocument(MarkupParser.java:393) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.MarkupParser.parse(MarkupParser.java:257) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parse(AbstractMarkupTemplateParser.java:230) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	... 48 common frames omitted
Caused by: org.thymeleaf.exceptions.TemplateProcessingException: Exception evaluating SpringEL expression: "session.getAttribute("loginuser").username" (template: "indexPage" - line 375, col 31)
	at org.thymeleaf.spring5.expression.SPELVariableExpressionEvaluator.evaluate(SPELVariableExpressionEvaluator.java:292) ~[thymeleaf-spring5-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.VariableExpression.executeVariableExpression(VariableExpression.java:166) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.SimpleExpression.executeSimple(SimpleExpression.java:66) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.Expression.execute(Expression.java:109) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.Expression.execute(Expression.java:138) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.Expression.execute(Expression.java:125) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.inline.AbstractStandardInliner.processExpression(AbstractStandardInliner.java:528) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.inline.AbstractStandardInliner.performInlining(AbstractStandardInliner.java:389) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.inline.AbstractStandardInliner.inline(AbstractStandardInliner.java:283) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.processor.StandardInliningCommentProcessor.doProcess(StandardInliningCommentProcessor.java:55) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.processor.comment.AbstractCommentProcessor.process(AbstractCommentProcessor.java:57) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.util.ProcessorConfigurationUtils$CommentProcessorWrapper.process(ProcessorConfigurationUtils.java:681) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.engine.ProcessorTemplateHandler.handleComment(ProcessorTemplateHandler.java:665) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.engine.TemplateHandlerAdapterMarkupHandler.handleComment(TemplateHandlerAdapterMarkupHandler.java:205) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.attoparser.AbstractChainedMarkupHandler.handleComment(AbstractChainedMarkupHandler.java:193) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.HtmlMarkupHandler.handleComment(HtmlMarkupHandler.java:195) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.AbstractChainedMarkupHandler.handleComment(AbstractChainedMarkupHandler.java:193) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.ParsingCommentMarkupUtil.parseComment(ParsingCommentMarkupUtil.java:54) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.MarkupParser.parseBuffer(MarkupParser.java:753) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.MarkupParser.parseDocument(MarkupParser.java:301) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	... 50 common frames omitted
Caused by: org.springframework.expression.spel.SpelEvaluationException: EL1004E: Method call: Method getAttribute(java.lang.String) cannot be found on type org.thymeleaf.context.WebEngineContext$SessionAttributesMap
	at org.springframework.expression.spel.ast.MethodReference.findAccessorForMethod(MethodReference.java:226) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:135) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:95) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.CompoundExpression.getValueRef(CompoundExpression.java:61) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:91) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.SpelNodeImpl.getValue(SpelNodeImpl.java:112) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:337) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.thymeleaf.spring5.expression.SPELVariableExpressionEvaluator.evaluate(SPELVariableExpressionEvaluator.java:265) ~[thymeleaf-spring5-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	... 69 common frames omitted

2022-02-23 09:42:12.438 ERROR 14216 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.thymeleaf.exceptions.TemplateInputException: An error happened during template parsing (template: "class path resource [templates/indexPage.html]")] with root cause

org.springframework.expression.spel.SpelEvaluationException: EL1004E: Method call: Method getAttribute(java.lang.String) cannot be found on type org.thymeleaf.context.WebEngineContext$SessionAttributesMap
	at org.springframework.expression.spel.ast.MethodReference.findAccessorForMethod(MethodReference.java:226) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:135) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:95) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.CompoundExpression.getValueRef(CompoundExpression.java:61) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:91) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.ast.SpelNodeImpl.getValue(SpelNodeImpl.java:112) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:337) ~[spring-expression-5.3.15.jar:5.3.15]
	at org.thymeleaf.spring5.expression.SPELVariableExpressionEvaluator.evaluate(SPELVariableExpressionEvaluator.java:265) ~[thymeleaf-spring5-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.VariableExpression.executeVariableExpression(VariableExpression.java:166) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.SimpleExpression.executeSimple(SimpleExpression.java:66) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.Expression.execute(Expression.java:109) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.Expression.execute(Expression.java:138) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.expression.Expression.execute(Expression.java:125) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.inline.AbstractStandardInliner.processExpression(AbstractStandardInliner.java:528) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.inline.AbstractStandardInliner.performInlining(AbstractStandardInliner.java:389) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.inline.AbstractStandardInliner.inline(AbstractStandardInliner.java:283) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.standard.processor.StandardInliningCommentProcessor.doProcess(StandardInliningCommentProcessor.java:55) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.processor.comment.AbstractCommentProcessor.process(AbstractCommentProcessor.java:57) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.util.ProcessorConfigurationUtils$CommentProcessorWrapper.process(ProcessorConfigurationUtils.java:681) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.engine.ProcessorTemplateHandler.handleComment(ProcessorTemplateHandler.java:665) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.engine.TemplateHandlerAdapterMarkupHandler.handleComment(TemplateHandlerAdapterMarkupHandler.java:205) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.attoparser.AbstractChainedMarkupHandler.handleComment(AbstractChainedMarkupHandler.java:193) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.HtmlMarkupHandler.handleComment(HtmlMarkupHandler.java:195) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.AbstractChainedMarkupHandler.handleComment(AbstractChainedMarkupHandler.java:193) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.ParsingCommentMarkupUtil.parseComment(ParsingCommentMarkupUtil.java:54) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.MarkupParser.parseBuffer(MarkupParser.java:753) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.MarkupParser.parseDocument(MarkupParser.java:301) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.attoparser.MarkupParser.parse(MarkupParser.java:257) ~[attoparser-2.0.5.RELEASE.jar:2.0.5.RELEASE]
	at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parse(AbstractMarkupTemplateParser.java:230) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parseStandalone(AbstractMarkupTemplateParser.java:100) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.engine.TemplateManager.parseAndProcess(TemplateManager.java:666) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1098) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1072) ~[thymeleaf-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.spring5.view.ThymeleafView.renderFragment(ThymeleafView.java:366) ~[thymeleaf-spring5-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.thymeleaf.spring5.view.ThymeleafView.render(ThymeleafView.java:190) ~[thymeleaf-spring5-3.0.14.RELEASE.jar:3.0.14.RELEASE]
	at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1401) ~[spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1145) ~[spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1084) ~[spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) ~[spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.15.jar:5.3.15]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.3.15.jar:5.3.15]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:655) ~[tomcat-embed-core-9.0.56.jar:4.0.FR]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.15.jar:5.3.15]
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.56.jar:4.0.FR]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.15.jar:5.3.15]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.15.jar:5.3.15]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.15.jar:5.3.15]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.15.jar:5.3.15]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.15.jar:5.3.15]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.15.jar:5.3.15]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) ~[tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:540) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:382) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:895) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1732) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.56.jar:9.0.56]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131]

2022-02-23 09:42:12.493 ERROR 14216 --- [nio-8080-exec-1] s.e.ErrorMvcAutoConfiguration$StaticView : Cannot render error page for request [/index] and exception [An error happened during template parsing (template: "class path resource [templates/indexPage.html]")] as the response has already been committed. As a result, the response may have the wrong status code.

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