Using ModelAttrbute annotation to submit object from jsp to controller

Question

I'm using spring mvc 3.1.0 with jsp/jstl. To submit object to my controller I'm using the ModelAttribute annotation and all is working fine. But, when I try to submit a complex object to my controller his value is null. This is my object model:

UorgVO.java

public class UorgVO {

    private String nom;
    private String nomAbrege;
    private UorgVO refUniteOrganisParent;

    //getters&Setters..
}

and there is my jsp page:

<form:form method="post" action="saveUorg.html"  modelAttribute="uorg" >
    <table>
        <tr>
            <th>Nom</th>
            <th>Nom abregé</th>
            <th>Unité père</th>
        </tr>
        <tr>
            <td><input  type="text" path="nom" name="nom"/></td>
            <td><input  type="text" path="nomAbrege" name="nomAbrege"/></td>
            <td>
                <select id="refUniteOrganisParent"
                        name="refUniteOrganisParent"
                    path="refUniteOrganisParent">
                    <option  value="null"> --- </option> 
                    <c:forEach items="${listeuos}" var="uorgg" varStatus="status" >
                        <option value="${uorgg}">${uorgg} </option> 
                    </c:forEach>
                </select>
            </td>
        </tr>
    </table> 
    <input type="submit" value="Enregistrer uorg"/> 
</form:form>

And my controller is:

@RequestMapping(value ="/saveUorg", method = RequestMethod.POST)
public ModelAndView saveUorg(@ModelAttribute("uorg") UorgVO uorg,BindingResult result) {

    System.out.println("My foreign attribute is:" +uorg.getRefUniteOrganisParent());
    return new ModelAndView("uorg_recherche");  
}   

And the printed value is null, but the other attributes of my object are submitted.

Thank's in advance for help

Answer 1

I solved the problem, i hope that it gonna help other users who has the same problem. By using the service of ConversionServiceFactoryBean. First, i used the ' form:select ' and 'form:input' , there is my new jsp code :

<td><form:input  path="email" type="text"/></td> 
<td>
<form:select path="refUniteOrganisParent.id" items="${listeuos}" itemValue="id" itemLabel="nom"/>
</td>

As you can see i retried the id value of the selected item.

Secondly i used this converter:

public class UorgConverter implements Converter<Long, UorgVO>{

@Autowired  
private UorgService uo;

@Override
public UorgVO convert(Long id) {

   // actions dealing with the service, to retrieve Uorg object from the id sended by the jsp page

    return uorgItem;        
  }

}

After that i configure my xml file by doing this:

<mvc:annotation-driven conversion-service="conversionService"/>

<bean id="conversionService" class="my.package.ConversionServiceFactoryBean">
<property name="converters">
    <list>
        <bean class="converter.package.location.UorgConverter"></bean>
        <!--List of my converters -->
    </list>
</property>
</bean>

Thank's to everybody who participates in this post to solve the problem.

Mouhie.