Spring MVC databinding using lists and checkboxes

Question

I know questions on this matter have been asked already, but none of the answers I found solved my problem.

I have a many-to-many relantionship on my database. I\'m usin

Answer 1

Apparently, the List comming from the checkbox was actually an array of Strings, which could not be converted to a List of Tags, as defined the model classes.

I solved my problem by creating a custom PropertyEditor, which would allow me to bind the checkboxes with the list of tags.

public class TagPropertyEditor extends PropertyEditorSupport {

    private TagService tagService;

    public TagPropertyEditor(TagService tagService){
        this.tagService = tagService;
    }

    @Override
    public String getAsText() {
        return ((Tag) getValue()).getId().toString();
    }

    @Override
    public void setAsText(String incomingId) throws IllegalArgumentException {
        Tag tag = tagService.getTag(Integer.valueOf(incomingId));
        setValue(tag);
    }
}

And then registering on my BookController:

//...
@InitBinder
public void initBinder(WebDataBinder binder){
    binder.registerCustomEditor(Tag.class, new TagPropertyEditor(tagService));
}

And this is the checboxes tag on my JSP:

 <form:checkboxes path="tags" 
                  items="${tags}"
                  itemLabel="description"
                  itemValue="id"/>