Model Attributes null with Thymeleaf-spring boot - spring-boot

Question

I have a weird error that is driving me crazy.
I have a Controller with two different Get Methods - for two different url mappings.
URL1 works perfectly fine, with URL2, I get
[THYMELEAF][http-nio-8080-exec-3] Exception processing template
"questionnaireForm": Error during execution of processor
'org.thymeleaf.standard.processor.attr.StandardEachAttrProcessor'
(questionnaireForm:10)
caused by
java.lang.NullPointerException: null at org.thymeleaf.context.WebSessionVariablesMap.hashCode(WebSessionVariablesMap.java:276) ~[thymeleaf-2.1.4.RELEASE.jar:2.1.4.RELEASE]
After hours of checking each line, it's clear that my Controller Get Method is adding a non-null object to the Model.addAttribute before calling the view.
I've also removed all of my code from the template and just added the following to troubleshoot:
<tr th:each="var : ${#vars}">
<td th:text="${var.key}"></td>
<td th:text="${var.value}"></td>
This is returning the same null error as well!
The only thing i could find on the web was a bug with Thymeleaf 2.1.4 that was caused by not having a HttpSession Object
https://github.com/thymeleaf/thymeleaf/issues/349
but then again, my URL1 works fine!
I haven't posted any code here because I'm not sure what else to post, please ask!
EDIT: Added Controller Code. /admin/questions is URL1 that works fine, '/admin/questionnaires' is URL2 that doesn't work.
#Controller
public class AdminController {
private QuestionRepository questionRepository;
private EQuestionnaireRepository eQuestionnaireRepository;
private EQuestionnaire eQuestionnaire;
#Autowired
public AdminController(QuestionRepository questionRepository,
EQuestionnaireRepository
eQuestionnaireRepository){
this.questionRepository = questionRepository;
this.eQuestionnaireRepository = eQuestionnaireRepository;
eQuestionnaire = eQuestionnaireRepository.findAll().get(0);
}
#RequestMapping(value = "/admin/questions", method=RequestMethod.GET)
public String questionForm(Model model) {
model.addAttribute("question", new Question());
return "questionForm";
}//-->This Works fine
#RequestMapping(value = "/admin/questions", method=RequestMethod.POST)
public String saveQuestion(#ModelAttribute Question newQuestion, BindingResult bindingResult, Model model) {
if( bindingResult.hasErrors())
{
System.out.println(bindingResult);
System.out.println("BINDING RESULTS ERROR");
return "questionForm";
}
questionRepository.save(newQuestion);
return "questionForm";
}
#RequestMapping(value = "/admin/Questionnaires", method=RequestMethod.GET)
public String QuestionnaireForm(Model model){
model.addAttribute("ListofQ",eQuestionnaire.getQuestionList());
return "questionnaireForm";
UPDATE: I changed over to thymeleaf 2.1.5-SNAPSHOT, and now I'm not getting the previously mentioned error - but a different error:
There was an unexpected error (type=Internal Server Error, status=500).
Exception evaluating SpringEL expression: "ask.questionText"
(questionnaireForm:13)
So now, the object reference is null in the template. It's not null when i put it into the Model (i've got System.out of the getQuestionText method inside the GET method, so thats confirmed)
This is the simple code I'm trying in the template:
<table>
<tr th:each= "ask : ${ListofQ}"></tr>
<tr th:text= "${ask.questionText}"></tr>
</table>
Here is the Question Object:
#Entity
#Table(name = "Questions")
public class Question {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Long ID;
private int sequence;
private String questionText;
private int weightage;
private String option1 = "option1";
private String option2 = "option2";
private String option3 = "option3";
public Question() {
}
public Long getID() {
return ID;
}
public void setID(Long iD) {
ID = iD;
}
public int getSequence() {
return sequence;
}
public void setSequence(int sequence) {
if (sequence > 0) this.sequence = sequence;
}
public String getQuestionText() {
return questionText;
}
public void setQuestionText(String questionText) {
this.questionText = questionText;
}
public int getWeightage() {
return weightage;
}
public void setWeightage(int weightage) {
this.weightage = weightage;
}
public void setOption1(String option1) {
this.option1 = option1;
}
public void setOption2(String option2) {
this.option2 = option2;
}
public void setOption3(String option3) {
this.option3 = option3;
}
public String getOption1() {
return option1;
}
public String getOption2() {
return option2;
}
public String getOption3() {
return option3;
}

Answer 1

output in "each" need to be in the same statement , i think this will work for you
<table>
<tr th:each= "ask : ${ListofQ}" th:text= "${ask.questionText}"></tr>
</table>

Answer 2

You are not returning the model object to the Thymeleaf.
Try something like this:
#RequestMapping(value = "/admin/Questionnaires", method=RequestMethod.GET)
public ModelAndView QuestionnaireForm(Model model){
return return new ModelAndView("questionnaireForm", "ListofQ",eQuestionnaire.getQuestionList());
}