Hibernate Spring - One to many - spring

Question

I am working on a JEE school project which is done with Spring and Hibernate. My tables are :
INFRACTION
id_infraction
description
DOSSIER
id_dossier
description
gravite
INFRACTIONDOSSIER
id_dossier
id_infraction
The application does work well for adding "infractions" and "dossiers" and retrieve them in jsp pages.
The app should be able to add multiple "infractions" to one "dossier", and that is where i'm blocked;
I'm learning One-to-many tags and implemented them in my "Dossier" Class, but as I want a form separated from the adding infraction and adding dossier ones, I don't know how to handle that.
Here is the code I added in my Dossier class :
#OneToMany
private Set<Infraction> infractions;
#OneToMany(cascade = CascadeType.ALL)
#JoinTable(
name = "DOSSIERINFRACTION",
joinColumns = #JoinColumn(name = "id_dossier"),
inverseJoinColumns = #JoinColumn(name = "id_infraction")
)
And my AppController class part handling adding Dossiers
/*
* Méthode d'ajout d'un dossier
*/
#RequestMapping(value = { "/new" }, method = RequestMethod.GET)
public String newDossier(ModelMap model) {
Dossier dossier = new Dossier();
model.addAttribute("dossier", dossier);
model.addAttribute("edit", false);
return "registration";
}
/*
* Gère l'envoi du POST pour l'ajout de dossier ainsi que la validation du
* formulaire
*
*/
#RequestMapping(value = { "/new" }, method = RequestMethod.POST)
public String saveDossier(#Valid Dossier dossier, BindingResult result, ModelMap model) {
if (result.hasErrors()) {
return "registration";
}
service.saveDossier(dossier);
model.addAttribute("success", "Dossier " + dossier.getNom() + " enregistré");
return "success";
}
JSP form to record a dossier
<form:form method="POST" modelAttribute="dossier">
<form:input type="hidden" path="id" id="id"/>
<table>
<tr>
<td><label for="nom">Nom: </label> </td>
<td><form:input path="nom" id="nom"/></td>
<td><form:errors path="nom" cssClass="error"/></td>
</tr>
<tr>
<td><label for="prenom">Prénom: </label> </td>
<td><form:input path="prenom" id="prenom"/></td>
<td><form:errors path="prenom" cssClass="error"/></td>
</tr>
<tr>
<td><label for="plaque">Plaque: </label> </td>
<td><form:input path="plaque" id="plaque"/></td>
<td><form:errors path="plaque" cssClass="error"/></td>
</tr>
<tr>
<td><label for="permis">Permis: </label> </td>
<td><form:input path="permis" id="permis"/></td>
<td><form:errors path="permis" cssClass="error"/></td>
</tr>
<tr>
<td colspan="3">
<c:choose>
<c:when test="${edit}">
<input type="submit" value="Mettre à jour"/>
</c:when>
<c:otherwise>
<input type="submit" value="Enregistrer"/>
</c:otherwise>
</c:choose>
</td>
</tr>
</table>
</form:form>
My question may seem a bit dumb, but how can I create a form which can add multiple infractions to dossier, and how to display the infractions from a dossier ?
Thank you,
Romain