codesmell.org

ahhh. doesn’t wicket offer a great model of programming webpages? isn’t it too easy to do things like this?

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add(new ListView("mylist",someList){
  @Override
  protected void populateItem(ListItem item){
    item.add(new PageLink("deleteThisEntry",new DeletePage(item.getModel())));
  }};
});
                

but wait PageLink(Page) is deprecated:

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/**
 * This constructor is ideal if a Page object was passed in from a previous Page. Construct a
 * link to the Page. Warning: DO NOT use this for constructing links to pages you didn't already
 * have an instance of. This constructor is strongly discouraged for anything other than linking
 * back to the same page.
 *
 * @param id
 *            See component
 * @param page
 *            The page
 * @deprecated rather than using this class/ constructor, use normal {@link Link links} and call
 *             setResponsePage in their {@link Link#onClick() onClick} methods.
 */
@Deprecated
public PageLink(final String id, final Page page)
                

why is that? if you look at it, it is very obvious.
because it is not lazy that means that you’re creating a big bunch of pages without needing them and all of them need to be serialized, maybe replicated etc.

it gets worse: when not reusing listitems, you’ll do that on every rendering of the example code!


even more worse, if your fellow programmer did something funny like:

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@SomeFunkyAnnotationForInterception
class DeletePage extends WebPage{
 public DeletePage(IModel objectToDelete){
   deleteObject(objectToDelete.getObject());
   setResponsePage(DeletionDonePage.class);
 }
 //...
}
                

which at leastcould
be a valid usecase.

so please, please, please – with sugar on top – replace

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new PageLink(id,new XYPage(...))
                

by

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new Link(id){
 public void onClick(){
  setResponsePage(new XYPage(...));
 }
}
                

in order to create the page only when needed.