Using Hibernate w/ Struts

mjessee · **Joined:** Mon Mar 08, 2004 8:57 pm **Posts:** 6

I'm trying to use Hibernate with Struts and am having a problem. Can I use the bean returned from Hibernate as my Form bean or do I need to create a duplicate Form bean and programmatically move the property values between them?

The problem I

flf-hibernate · **Joined:** Tue Mar 09, 2004 12:01 am **Posts:** 9

Struts forms are not part of the model of MVC, therefore you really should not store them in a DB. You can view them as struts DTO, they help for validating the user input, that's all (cf any book on struts).

That's a pain to write and make a correspondance between your stored objects and struts forms, and that's one of the reasons why I don't really like struts.

Lovecraft · **Joined:** Tue Mar 09, 2004 11:17 pm **Posts:** 8

You can easily use BeanUtils.copyProperties() to copy properties from your beans to your forms, and vice-versa. It will even convert data types automatically for you.

micho2001 · **Posted:** Mon Mar 15, 2004 10:44 am

How would this work for you?

Code:

public class MyForm extends ActionForm
{
//Hibernate persisted java object 
private MyPOJO myPOJO;

public void setMyPOJO(MyPOJO mp){
myPOJO = mp; 
}

public void getMyPOJO(){
return myPOJO;
}

}

In a jsp page when using struts forms:

For this to work your attributes must have setter and getters

Code:

<html:form action="myACTION" name="MyForm">
<html:text property="myPOJO.someAttribute" />
</html:form>

Hope it helps...

anthony · **Posted:** Mon Mar 15, 2004 11:06 am

and what happens when you call
MyForm.myPOJO.setSomeAttribute() directly on jsp ???
looks dangerous

i use this solution, data tranfer objects are more secure for the presentation layer... it's only my point of view
i'm doing something like Lovecraft

Quote:

You can easily use BeanUtils.copyProperties() to copy properties from your beans to your forms, and vice-versa. It will even convert data types automatically for you.

micho2001 · **Posted:** Mon Mar 15, 2004 11:20 am

uhm... Im not sure about the dangers you talk about....

Mostly when I use it I rely on validation.

What I like about your approach is that it can handle object types (e.g Dates) easily.

What I dont like is replicating properties in the Action form

anthony · **Posted:** Mon Mar 15, 2004 11:31 am

you can also use DynaForm with copy properties

Have you tried pure jsp code <% persistentObjets.set... %> and look what happens next with the referenced objects on session.flush() for example?

micho2001 · **Posted:** Mon Mar 15, 2004 11:35 am

O.K. I get your point and it's valid.

I will have a look at the dynaform. Never used them up to now, the approach I mentioned works well provided you use the html:form tags though, wouldnt you agree?

anthony · **Posted:** Mon Mar 15, 2004 11:58 am

try to take a look at DynaValidatorForm, it works great a generate some javascript validation.

I prefer not injecting persistent object in the view...

l.masini · **Posted:** Tue Mar 16, 2004 10:30 am

I heavily use Hibernate and Struts in my project and
1) I use directly Model Object if I only have to print their values on the output. All the formatting is done with the formatKey of the bean:write tag and all concern are separated.
2) When I have some inputs I use DynaValidatorForm, and on the Control Layer (aka Struts Actions) I copy the values using copyProperties
I can give you more detail if you are interested.

d10n2000 · **Joined:** Mon Jan 12, 2004 2:24 am **Posts:** 16

delpove writes:
> and what happens when you call
> MyForm.myPOJO.setSomeAttribute() directly on jsp ???

Does it means that Hibernate Persisted Java Object (in the example it's MyPojo is *not* disconnected? If as you say, MyForm.myPOJO.setSomeAttribute() is being called directly on jsp, the values in database's table for that particular object would be updated?

At first I plan to utilize Hibernate Persisted Java Object for DTO (instead of creating another Value Object), but now I have some doubts regarding issue above.

Please help with this.

regards,
Dion

michael · **Posted:** Thu Apr 29, 2004 3:45 am

If you use the Open Session in View pattern, you can modify and lazy-load objects just like everywhere else in the session scope. I would rather recommend sticking to an MVC architecture though, and just use OSiV only for lazy loading in the view layer.

d10n2000 · **Joined:** Mon Jan 12, 2004 2:24 am **Posts:** 16

Michael, thanks for the pointer.
right now I'm reading http://forum.hibernate.org/viewtopic.php?t=927886, I must admit that I don't really understand it very well yet :(
BTW, I do want to use it for View only, though.

regards,
dion