How do I keep entities (or their associations) attached to the current persistence context across multiple requests (using Wicket & JPA)?

Question

I am working on a Wicket-based web app on Java EE.

I am trying to find a way to ensure that any entities used as model objects are always attached to the current EntityM

Answer 1

I cases like this I usually create a DTO keeping all the data I need to create an entity. If you need to reference existing entities - pass them to your forms/panels as separate models. When the form is submitted you can then:

• perform the validation
• create a new entity from DTO that was edited
• inject references to other entities that you have stored in those separate LDM models.
• persist the entity.

It's a bit of hassle but does actually work.

Conversations spanning multiple requests are not available in pure wicket and probably will never be - this is not wicket's area.

Seam supports long conversations and it does support wicket (I have never used seam - I cannot advice you on this one).