Raible's Wiki: POJOsToForms

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This is from a [discussion|http://www.mail-archive.com/struts-user%40jakarta.apache.org/msg69836.html] on the struts-user mailing list. I'm continuing it here because I want to propose a new idea: __only converting ActionForms to POJOs__. By this, I mean to say that I'd like to retrieve and display POJOs on the UI, and capture their information (as ActionForms) when saving the form. The reason I want to do this is because of Hibernate's Lazy Loading feature. Basically, Hibernate allows you to load children of an object, i.e. Resumes of a User, when the {{getResumes()}} method is called on User.

This is from a [discussion|http://www.mail-archive.com/struts-user%40jakarta.apache.org/msg69836.html] on the struts-user mailing list. I'm continuing it here because I want to propose a new idea:

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When using BeanUtils.copyProperties() to convert a POJO to an ActionForm, the {{getResumes()}} method is called. However, I don't want this. I'd rather the getResumes() method is called when I call it in my code. Therefore, I'm thinking that passing the POJO to the view is the best solution. Because I'm using the open-session-in-view pattern, those lazy collections are still available while the JSP is being rendered.

__Send your [POJO]s to the UI rather than converting them to ActionForms first.__

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By this, I mean to say that I'd like to retrieve and display POJOs on the UI, and then capture their information (as ActionForms) when saving the form. The reason I want to do this is because of Hibernate's Lazy Loading feature and formatting Dates. Basically, Hibernate allows you to load children of an object lazily (i.e. resumes of a User), when the {{getResumes()}} method is called.

The issue I'm seeing right now with lazily-loaded properties is that they're loaded when using BeanUtils.copyProperties() is called. I use this to convert POJOs to ActionForms, and consequently the {{getResumes()}} method is called. However, I don't want this. I'd rather the getResumes() method is called when I call it in my code (rather than by a 3rd party conversion utility). Therefore, I'm thinking that passing the POJO to the view is the best solution. Because I'm using the [open-session-in-view pattern|http://hibernate.bluemars.net/43.html], those lazy collections are still available while the JSP is being rendered.

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''You might also be interested in [my blog entry on the subject|http://www.raibledesigns.com/page/rd/20030619#sending_pojos_to_the_ui].''

''Are you saying that you would populate the form manually in the view?'' ~ [mojavelinux]

I suggest looking at Struts' __Nested__ taglib. It does set properties if complex DTO objects

and does not require (semi)manual conversion between strings and actual data types.

With little wrapper to BeanUtilities, which registers a Date handler with desired formatting pattern, it allows correct handling of dates.

__Related Pages:__

* [DTOInForm]

* [Nested Extension|http://keyboardmonkey.com/next/index.jsp]

__Comments:__

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I know it's not really useful to you, but WebWork gives you this natively. It's one of the big differences between WW and Struts, in that with WebWork you can make true model-driven actions, and then use them in your form.

For example a form field called

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