Command object in the onSubmit method of SimpleFormController

[sinnus]

Why the name of a bind object is named as command? I think command is a pattern and a bind object is a form.
For example:

public class BlahblahController extends SimpleFormController {

    protected ModelAndView onSubmit(
        HttpServletRequest request,
        HttpServletResponse response,
        Object command,
        BindException errors) throws ServletException, IOException {
...

Thanx.

[Marten Deinum]

Call me stupid but I really don't understand your question.

In Spring commandObject and formBacking Object can be used accordingly. Is has nothing to do with the Command Pattern you mention.

[sinnus]

Call me stupid but I really don't understand your question.

In Spring commandObject and formBacking Object can be used accordingly. Is has nothing to do with the Command Pattern you mention.

Why name of parameter is command?

[Marten Deinum]

Because the method is called formBackingObject and it returns a Command Object (not in anyway related to the Command Pattern you mentioned). In Spring the formBackingObject is named a command object and hence the name is command.

[sinnus]

Because the method is called formBackingObject and it returns a Command Object (not in anyway related to the Command Pattern you mentioned). In Spring the formBackingObject is named a command object and hence the name is command.

Call me stupid but I think it's not a clear explanation.

[Marten Deinum]

Read this .

The controller is a CommandController the root of all these controllers is the BaseCommandController. The method used to create the object which this Controller works on/with is getCommand.

Basicly everything which extends BaseCommandController is a command controller. Hence the naming of the property.

Although it might become confusing when looking at the AbstractFormController which is a sub class of the BaseCommandController. This delegates the creating of a command object to the formBackingObject. method. But still it is a command Controller.

[sinnus]

As I see the command is a simple JavaBean which can be shown on a jsp. Form is a JavaBean which can be shown on a jsp and submitted (according to http://static.springframework.org/sp...oller-command).

For the avoidance of misunderstanding it should be a bit better to name a command parameter as anyObject or some else.

[Marten Deinum]

Why? It IS the command which represents the form. The command and form are the same there is no difference.

[sinnus]

Why? It IS the command which represents the form. The command and form are the same there is no difference.

We're almost there...
My main question is why the object named as command? This name is not meaning for programmers I think. Form is more convenient name.

[Marten Deinum]

No it isn't because the command doesn't have to be a form.