1

I am trying to set up a java Spring application that will receive data from a website and display it in a thymeleaf template. The data is received successfully and it is populating the object in my app with the appropriate results. However, when trying to display those results as text in html the thymeleaf crashes. If I remove the sections of code where I have the data to be displayed, the html renders just fine. Here is my controller and POJO class for the data:

package webtech.twlab;

import org.jetbrains.annotations.NotNull;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;
import org.springframework.ui.Model;
import org.springframework.web.servlet.ModelAndView;


@Controller
@CrossOrigin(origins = "http://localhost:63343")
public class AnswersController {


//    private Answers answersList;
    @PostMapping("/answers")
    @ResponseBody
    public ModelAndView handleAnswers(@RequestBody @NotNull Answers answers){
        System.out.println(answers.getAnswer3());
        ModelAndView mav = new ModelAndView("answers");
//        answersList = answers;
        mav.addObject("answersList", answers);
        return mav;
    }

//    @RequestMapping("/answers")
//    public String getAnswers(Model model){
//        model.addAttribute("answersList", answersList);
//        return "answers";
//    }


}


package webtech.twlab;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;

import java.util.ArrayList;

public class Answers {

    private String answer1;
    private String answer2;
    private String answer3;
    private String answer4;
    private String answer5;
    private String answer6;

    @JsonCreator
    public Answers(@JsonProperty("r1") String answer1, @JsonProperty("r2") String answer2,@JsonProperty("r3") String answer3,@JsonProperty("r4") String answer4,@JsonProperty("r5") String answer5,@JsonProperty("r6") String answer6) {
        this.answer1 = answer1;
        this.answer2 = answer2;
        this.answer3 = answer3;
        this.answer4 = answer4;
        this.answer5 = answer5;
        this.answer6 = answer6;
    }



    public String getAnswer1() {
        return answer1;
    }

    public void setAnswer1(String answer1) {
        this.answer1 = answer1;
    }

    public String getAnswer2() {
        return answer2;
    }

    public void setAnswer2(String answer2) {
        this.answer2 = answer2;
    }

    public String getAnswer3() {
        return answer3;
    }

    public void setAnswer3(String answer3) {
        this.answer3 = answer3;
    }

    public String getAnswer4() {
        return answer4;
    }

    public void setAnswer4(String answer4) {
        this.answer4 = answer4;
    }

    public String getAnswer5() {
        return answer5;
    }

    public void setAnswer5(String answer5) {
        this.answer5 = answer5;
    }

    public String getAnswer6() {
        return answer6;
    }

    public void setAnswer6(String answer6) {
        this.answer6 = answer6;
    }



}

The thymeleaf template:

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Answers</title>
</head>
<body>
<h1>Answers:</h1>
<p>Answer 1: <span th:text="${answersList.answer1}">-</span></p>
<p>Answer 2: <span th:text="${answersList.answer2}">-</span></p>
<p>Answer 3: <span th:text="${answersList.answer3}">-</span></p>
<p>Answer 4: <span th:text="${answersList.answer4}">-</span></p>
<p>Answer 5: <span th:text="${answersList.answer5}">-</span></p>
<p>Answer 6: <span th:text="${answersList.answer6}">-</span></p>
</body>
</html>

Also, when looking at the dev console in the browser, there is a status 405 get method at the domain localhost:8080 file "answers"

I have set up a web confiuguration to allow POST, GET, PUT, DELETE methods inside the project, the application properties are set up properly, also pom.xml looks fine. It seems just that tymeleaf is unable to get the data from inside the answerList object. I will underline that the data is being received successfully and I can print it in my IDE console to see if it is not null.

Here are the errors i get logs from the console:

2023-04-04T22:25:10.171+03:00 ERROR 17108 --- [nio-8080-exec-2] org.thymeleaf.TemplateEngine             : [THYMELEAF][http-nio-8080-exec-2] Exception processing template "answers": An error happened during template parsing (template: "class path resource [templates/answers.html]")

org.thymeleaf.exceptions.TemplateInputException: An error happened during template parsing (template: "class path resource [templates/answers.html]")
    at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parse(AbstractMarkupTemplateParser.java:241) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parseStandalone(AbstractMarkupTemplateParser.java:100) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.engine.TemplateManager.parseAndProcess(TemplateManager.java:666) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1103) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1077) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.spring6.view.ThymeleafView.renderFragment(ThymeleafView.java:372) ~[thymeleaf-spring6-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.spring6.view.ThymeleafView.render(ThymeleafView.java:192) ~[thymeleaf-spring6-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1415) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1159) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1098) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:974) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1011) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:903) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:537) ~[tomcat-embed-core-10.1.7.jar:6.0]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:631) ~[tomcat-embed-core-10.1.7.jar:6.0]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:205) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-6.0.7.jar:6.0.7]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.7.jar:6.0.7]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:166) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:115) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:390) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:894) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1741) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at java.base/java.lang.Thread.run(Thread.java:1589) ~[na:na]
Caused by: org.attoparser.ParseException: Exception evaluating SpringEL expression: "answersList.answer1" (template: "answers" - line 9, col 20)
    at org.attoparser.MarkupParser.parseDocument(MarkupParser.java:393) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupParser.parse(MarkupParser.java:257) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parse(AbstractMarkupTemplateParser.java:230) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    ... 40 common frames omitted
Caused by: org.thymeleaf.exceptions.TemplateProcessingException: Exception evaluating SpringEL expression: "answersList.answer1" (template: "answers" - line 9, col 20)
    at org.thymeleaf.spring6.expression.SPELVariableExpressionEvaluator.evaluate(SPELVariableExpressionEvaluator.java:292) ~[thymeleaf-spring6-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.VariableExpression.executeVariableExpression(VariableExpression.java:166) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.SimpleExpression.executeSimple(SimpleExpression.java:66) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.Expression.execute(Expression.java:109) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.Expression.execute(Expression.java:138) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.processor.AbstractStandardExpressionAttributeTagProcessor.doProcess(AbstractStandardExpressionAttributeTagProcessor.java:144) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.processor.element.AbstractAttributeTagProcessor.doProcess(AbstractAttributeTagProcessor.java:74) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.processor.element.AbstractElementTagProcessor.process(AbstractElementTagProcessor.java:95) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.util.ProcessorConfigurationUtils$ElementTagProcessorWrapper.process(ProcessorConfigurationUtils.java:633) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.engine.ProcessorTemplateHandler.handleOpenElement(ProcessorTemplateHandler.java:1314) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.engine.TemplateHandlerAdapterMarkupHandler.handleOpenElementEnd(TemplateHandlerAdapterMarkupHandler.java:304) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.templateparser.markup.InlinedOutputExpressionMarkupHandler$InlineMarkupAdapterPreProcessorHandler.handleOpenElementEnd(InlinedOutputExpressionMarkupHandler.java:278) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.inline.OutputExpressionInlinePreProcessorHandler.handleOpenElementEnd(OutputExpressionInlinePreProcessorHandler.java:186) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.templateparser.markup.InlinedOutputExpressionMarkupHandler.handleOpenElementEnd(InlinedOutputExpressionMarkupHandler.java:124) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.attoparser.HtmlElement.handleOpenElementEnd(HtmlElement.java:109) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.HtmlMarkupHandler.handleOpenElementEnd(HtmlMarkupHandler.java:297) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupEventProcessorHandler.handleOpenElementEnd(MarkupEventProcessorHandler.java:402) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.ParsingElementMarkupUtil.parseOpenElement(ParsingElementMarkupUtil.java:159) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupParser.parseBuffer(MarkupParser.java:710) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupParser.parseDocument(MarkupParser.java:301) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    ... 42 common frames omitted
Caused by: org.springframework.expression.spel.SpelEvaluationException: EL1007E: Property or field 'answer1' cannot be found on null
    at org.springframework.expression.spel.ast.PropertyOrFieldReference.readProperty(PropertyOrFieldReference.java:213) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.PropertyOrFieldReference.getValueInternal(PropertyOrFieldReference.java:104) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.PropertyOrFieldReference$AccessorLValue.getValue(PropertyOrFieldReference.java:405) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:92) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.SpelNodeImpl.getValue(SpelNodeImpl.java:112) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:338) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.thymeleaf.spring6.expression.SPELVariableExpressionEvaluator.evaluate(SPELVariableExpressionEvaluator.java:265) ~[thymeleaf-spring6-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    ... 61 common frames omitted

2023-04-04T22:25:10.176+03:00 ERROR 17108 --- [nio-8080-exec-2] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: org.thymeleaf.exceptions.TemplateInputException: An error happened during template parsing (template: "class path resource [templates/answers.html]")] with root cause

org.springframework.expression.spel.SpelEvaluationException: EL1007E: Property or field 'answer1' cannot be found on null
    at org.springframework.expression.spel.ast.PropertyOrFieldReference.readProperty(PropertyOrFieldReference.java:213) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.PropertyOrFieldReference.getValueInternal(PropertyOrFieldReference.java:104) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.PropertyOrFieldReference$AccessorLValue.getValue(PropertyOrFieldReference.java:405) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:92) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.ast.SpelNodeImpl.getValue(SpelNodeImpl.java:112) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:338) ~[spring-expression-6.0.7.jar:6.0.7]
    at org.thymeleaf.spring6.expression.SPELVariableExpressionEvaluator.evaluate(SPELVariableExpressionEvaluator.java:265) ~[thymeleaf-spring6-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.VariableExpression.executeVariableExpression(VariableExpression.java:166) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.SimpleExpression.executeSimple(SimpleExpression.java:66) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.Expression.execute(Expression.java:109) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.expression.Expression.execute(Expression.java:138) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.processor.AbstractStandardExpressionAttributeTagProcessor.doProcess(AbstractStandardExpressionAttributeTagProcessor.java:144) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.processor.element.AbstractAttributeTagProcessor.doProcess(AbstractAttributeTagProcessor.java:74) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.processor.element.AbstractElementTagProcessor.process(AbstractElementTagProcessor.java:95) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.util.ProcessorConfigurationUtils$ElementTagProcessorWrapper.process(ProcessorConfigurationUtils.java:633) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.engine.ProcessorTemplateHandler.handleOpenElement(ProcessorTemplateHandler.java:1314) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.engine.TemplateHandlerAdapterMarkupHandler.handleOpenElementEnd(TemplateHandlerAdapterMarkupHandler.java:304) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.templateparser.markup.InlinedOutputExpressionMarkupHandler$InlineMarkupAdapterPreProcessorHandler.handleOpenElementEnd(InlinedOutputExpressionMarkupHandler.java:278) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.standard.inline.OutputExpressionInlinePreProcessorHandler.handleOpenElementEnd(OutputExpressionInlinePreProcessorHandler.java:186) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.templateparser.markup.InlinedOutputExpressionMarkupHandler.handleOpenElementEnd(InlinedOutputExpressionMarkupHandler.java:124) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.attoparser.HtmlElement.handleOpenElementEnd(HtmlElement.java:109) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.HtmlMarkupHandler.handleOpenElementEnd(HtmlMarkupHandler.java:297) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupEventProcessorHandler.handleOpenElementEnd(MarkupEventProcessorHandler.java:402) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.ParsingElementMarkupUtil.parseOpenElement(ParsingElementMarkupUtil.java:159) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupParser.parseBuffer(MarkupParser.java:710) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupParser.parseDocument(MarkupParser.java:301) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.attoparser.MarkupParser.parse(MarkupParser.java:257) ~[attoparser-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parse(AbstractMarkupTemplateParser.java:230) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.templateparser.markup.AbstractMarkupTemplateParser.parseStandalone(AbstractMarkupTemplateParser.java:100) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.engine.TemplateManager.parseAndProcess(TemplateManager.java:666) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1103) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.TemplateEngine.process(TemplateEngine.java:1077) ~[thymeleaf-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.spring6.view.ThymeleafView.renderFragment(ThymeleafView.java:372) ~[thymeleaf-spring6-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.thymeleaf.spring6.view.ThymeleafView.render(ThymeleafView.java:192) ~[thymeleaf-spring6-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1415) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1159) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1098) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:974) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1011) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:903) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:537) ~[tomcat-embed-core-10.1.7.jar:6.0]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) ~[spring-webmvc-6.0.7.jar:6.0.7]
    at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:631) ~[tomcat-embed-core-10.1.7.jar:6.0]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:205) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-6.0.7.jar:6.0.7]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.7.jar:6.0.7]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:166) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:115) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:390) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:894) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1741) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-10.1.7.jar:10.1.7]
    at java.base/java.lang.Thread.run(Thread.java:1589) ~[na:na]
Crinu Dimitriu
  • 11
  • 3
  • Your controller does not match what you are describing. The `@ResponseBody` annotation means that your controller does not process a Thymeleaf template, instead it serializes the returned value as JSON. Without knowing exactly what your controller is doing, it's hard to tell why you are getting the error. – Metroids Apr 05 '23 at 01:33

1 Answers1

0

So the issue was that initially before sending the data to the Spring server the object answers was null and Thymeleaf did not accept null objects unless I add some changes to the template:

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Answers</title>
</head>
<body>
<h1>Answers:</h1>
<p>Answer 1: <span th:text="${answers?.answer1} ?: '-'"></span></p>
<p>Answer 2: <span th:text="${answers?.answer2} ?: '-'"></span></p>
<p>Answer 3: <span th:text="${answers?.answer3} ?: '-'"></span></p>
<p>Answer 4: <span th:text="${answers?.answer4} ?: '-'"></span></p>
<p>Answer 5: <span th:text="${answers?.answer5} ?: '-'"></span></p>
<p>Answer 6: <span th:text="${answers?.answer6} ?: '-'"></span></p>
</body>
</html>

Now it is working just fine

Crinu Dimitriu
  • 11
  • 3