Question

I have a game and a developer. The game has a set of developers. I want to create a form where I can add a game to the database. In the form I enter the name, price and check the developers. So i create a checkbox for every developer. However when I check those the page just seems to refresh. When I debug it seems that my controller never gets to the doSubmitAction function. When I leave out the checkboxes everything works as it is supposed to.
Is spring unable to create the collection? I don’t understand fully what is happening behind the scenes of Spring. This is my first project I’m creating using spring.

Here is my form:

 <form:form method="POST" commandName="game" >
                    <table>
                        <tr>
                            <td>
                                Name
                            </td>
                            <td>
                                <form:input path="gameNaam" size="20" />
                            </td>
                        </tr>

                        <tr>
                            <td>Choose Developers</td>
                            <td>
                                <form:checkboxes id="selectdeveloper" items="${developers}" path="developers" itemLabel="naam" />

                            </td>
                        </tr>
                        <tr>
                            <td>
                               Price
                            </td>
                            <td>
                                <form:input path="prijs" size="10" />
                            </td>
                        </tr>
                        <tr>
                            <td>

                                <input type="submit" value="Add" />

                            </td>
                            <td></td>
                        </tr>

                    </table>
                </form:form>

And the formController:

public class GameFormController extends SimpleFormController {

    private GameOrganizer gameOrganizer;

    public GameFormController() {
       setCommandClass(Game.class);
       setCommandName("game");
       setFormView("AddGame");
       setSuccessView("forward:/Gamedatabase.htm");
   }

    public void setGameOrganizer(GameOrganizer gameOrganizer){
       this.gameOrganizer=gameOrganizer;
    }

    @Override
    protected Object formBackingObject(HttpServletRequest request) throws Exception {
       Game game = null;
       long id = ServletRequestUtils.getLongParameter(request, "id");
       if(id<=0){
           game = new Game();
       }else{
           game = gameOrganizer.getGame(id);
       }
       return game;
    }



    @Override
    protected void doSubmitAction(Object command) throws Exception {

        Game game = (Game) command;
        if(game.getId()<=0){
            gameOrganizer.addGame(game);
        }else{
           gameOrganizer.update(game);

       }

   }

   @Override
   protected Map referenceData(HttpServletRequest request) throws Exception {
       Set<Developer> developers = gameOrganizer.getAllDevelopers();
       HashMap<String, Object> map = new HashMap<String, Object>();
      map.put("developers", developers);
      return map;
   }


}

Answer 1

Ok so apparently I had to make a propertyEditor for Developer.
There is a good explanation on this site:

http://static.springsource.org/spring/docs/2.0.x/reference/validation.html

Edit extra information:

So apparently when you check a checkbox it will give you the value as a string.
Ofcourse the Collection had to be made with developer objects.

So I created a developerEditor:

package domainmodel;

import java.beans.PropertyEditorSupport;

public class DeveloperEditor extends PropertyEditorSupport {

    private GameOrganizer gameOrganizer;


    public void setGameOrganizer(GameOrganizer gameOrganizer) {
        this.gameOrganizer = gameOrganizer;
    }

    @Override
    public void setAsText(String id) {
        long id2 = Long.parseLong(id);
        Developer type = gameOrganizer.getDeveloper(id2);
        setValue(type);
    }
}

And with the checkboxes I gave as itemvalue the id of the object

<form:checkboxes id="selectdeveloper" items="${allDevelopers}" itemValue="id" path="developers" itemLabel="name" />

Then in the formcontroller I override the initBinder method.
So that when I Spring has to fill in a developer object it will first convert it from string to a Developer Object using my editor.

 private DeveloperEditor developerEditor;

 public void setDeveloperEditor(DeveloperEditor developerEditor){
    this.developerEditor = developerEditor;
    developerEditor.setGameOrganizer(gameOrganizer);
}

 @Override
protected void initBinder(HttpServletRequest request, ServletRequestDataBinder binder) {
    binder.registerCustomEditor(Developer.class, developerEditor);
}

That’s it folks.
If anyone has any questions I will be glad to answer them.