I have a class Account persisted by Hibernate. I want to use an Hibernate Session in the default constructor of class Account, in order to load complementary objects.

But it doesn't work because when Hibernate creates the SessionFactory, Hibernate tries to create an instance of Account by calling the default constructor. As the SessionFactory is not already created, the default constructor can't open a Session and raises an exception...

So, I have two questions:

1) Why Hibernate needs to create an instance of each persisted class during the creation of a SessionFactory?

2) Is it possible to create a SessionFactory without this behavior?

Thank you for your answers !

Why in gods name do you need a Session in your constructor? This is a very bad design decision.

The Account class has a "category" property. This property can take one value in a list of several possible values.

I want to initialize a "categoryList" property in the default constructor, in order to provide a "getCategoryList()" method returning the list of all possible values for the "category" property.

I "feel" this is a bad design decision, but I don't really understand why. Can you explain your point of view.

Out of curiosity, I'm already interested to know why Hibernate needs to create an instance of each persisted class during creation of a SessionFactory.

Use the "typesafe enumeration" pattern for this.

Read this book: http://developer.java.sun.com/developer ... ctivejava/

Chapter 5, Item 21, it is available online. Hibernate directly supports the mapping of enumeration classes, see the Hibernate documentation, "persistent enumerations".

This a good idea, but the property "categories" holding the list of possible values for the property "category" is not constant. In fact, the categories are stored in the databse and persisted with a Category class. So, the property "categories" is just a kind of shortcut to find all instances of Category class.

I chose this design to have an "all-in-one" model (the Account class) that can be used in my view (a Swing panel) with a getCategory() to retrieve the current value and a getCategories() to retrieve list of possible values.