Creating HTML form with Spring+Hibernate - spring

Question

I have 3 classes:
First class, is an entity, that stores String variable:
#Entity
#Table(name = "mods_langs_texts", catalog = "artfunpw")
#Cache(usage = CacheConcurrencyStrategy.TRANSACTIONAL)
public class ModsLangsTexts implements java.io.Serializable {
#Column(name = "Title", nullable = false, length = 300)
public String getTitle() {
return this.title;
}
Second entity is for relations:
#Entity
#Table(name = "mods_langs_texts_relations", catalog = "artfunpw")
#Cache(usage = CacheConcurrencyStrategy.TRANSACTIONAL)
public class ModsLangsTextsRelations implements java.io.Serializable {
#ManyToOne(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
#JoinColumn(name = "textId", nullable = false)
public ModsLangsTexts getModsLangsTexts() {
return this.modLangsTexts;
}
And the third entity is the main class:
#Entity
#Table(name = "mods", catalog = "artfunpw")
#Cache(usage = CacheConcurrencyStrategy.TRANSACTIONAL)
public class Mod implements java.io.Serializable {
#OneToMany(fetch = FetchType.EAGER, mappedBy = "mod")
#Cache(usage = CacheConcurrencyStrategy.TRANSACTIONAL)
public Set<ModsLangsTextsRelations> getModsLangsTextsRelationses() {
return this.modsLangsTextsRelationses;
}
I am trying to create HTML form with the code:
m.addAttribute("formClass", mod);
And HTML code:
<p th:text="${formClass.modsLangsTextsRelationses.toArray()[0].getModsLangsTexts().title}" />
<form action="" th:object='${formClass}' method="POST">
<input type="hidden" th:field='*{id}' />
Title: <input type="text" th:field='${formClass.modsLangsTextsRelationses.toArray()[0].getModsLangsTexts().title}' />
<br />
But it fails with error:
2017-10-13 14:33:56.661 ERROR 4744 --- [nio-8080-exec-9] org.thymeleaf.TemplateEngine : [THYMELEAF][http-nio-8080-exec-9] Exception processing template "mods/editPages/editModPage": Error during execution of processor 'org.thymeleaf.spring4.processor.attr.SpringInputGeneralFieldAttrProcessor' (mods/editPages/editModPage:57)
Where line 57 is the line with code:
Title: <input type="text" th:field='${formClass.modsLangsTextsRelationses.toArray()[0].getModsLangsTexts().title}' />
In the same time, code
<p th:text="${formClass.modsLangsTextsRelationses.toArray()[0].getModsLangsTexts().title}" />
works fine.
How can I access inner objects from HTML form code with Spring+Hibernate+Thymeleaf?

Answer 1

Have a look at the thymeleaf tutorial :
The th:field is a field reference to a command object you declare on the form tag thanks to the th:object attribute
From the tutorial :
<form action="#" th:action="#{/seedstartermng}" th:object="${seedStarter}" method="post">
<input type="text" th:field="*{datePlanted}" />
</form>
Adapted to your case it would be something like :
<form action="#" th:action="#{???}" th:object="${formClass.modsLangsTextsRelationses.toArray()[0].getModsLangsTexts()}" method="post">
<input type="text" th:field="*{title}" />
</form>
I have a doubt it will work this way. Have a look at section 7.6 : dynamic fields