Spring MVC error in performing Binding of checkboxes on a list of objects

Question

I have the following piece of code in my .jsp, in which the objective is to dynamically list a passenger list per customer.

<f:form id="service-item-form" action="${action}" modelAttribute="serviceItem" method="post">
   <ul id="list-of-passenger-service-item" class="list-cadastro">
      <c:choose>
         <c:when test="${empty customer.passenger}">
            <li>
               <b>O Cliente não possui passageiros vinculados.</b>
            </li>
         </c:when>
         <c:otherwise>
            <f:checkboxes items="${customer.passenger}" path="passenger" element="li" itemValue="id"/>
         </c:otherwise>
      </c:choose>
   </ul>
</f:form>

The bind is held in my bean OpenService.java in the Passenger attribute, as shown below:

@Entity
@Table(name = "open_service")
public class OpenService implements Serializable{

    //other attributes

    @ManyToMany(fetch = FetchType.EAGER)
    @JoinTable(name = "service_passenger", joinColumns = @JoinColumn(name = "service_id"), inverseJoinColumns = @JoinColumn(name = "passenger_id"))
    private List<Passenger> passenger;

   //Getter and Setter
}

Finally it fires an action with the following signature:

@RequestMapping(value = "/add-service/{id}", method = RequestMethod.POST)
public String addService(@ModelAttribute("serviceItem") OpenService openService, @PathVariable Long id) {

   //business rules

   return "redirect:/acme"

}

But the problem is it always triggers the error below conversion, but as far as I know natively the Spring MVC is able to perform bind with list type objects

Field error in Object 'serviceItem' on field 'Passenger': Rejected value [7]; codes [typeMismatch.serviceItem.Passenger,typeMismatch.Passenger,typeMismatch.java.util.List,typeMismatch]; Arguments [org.springframework.context.support.Defaultmessagesourceresolvable: codes [serviceItem.Passenger,Passenger]; Arguments []; default message [Passenger]]; default message [Failed to Convert Property value of type 'java.lang.String' to required type 'java.util.List' for Property 'Passenger'; nested Exception is java.lang.Illegalstateexception: Cannot Convert value of type [java.lang.String] to required type [br.com.joocebox.model.Passenger] for Property 'Passenger[0]': no matching Editors or Conversion Strategy found]

Answer 1

Buddy, I’ve never seen bind with a list before. What is done is bind to an attribute and add that attribute to a list and manipulate it at your pleasure.

Try Bind to a Passenger Client and add that object to the list and make the necessary modifications.