BC4J with Struts using EditAction's create method.

Question

Hi,
I am using BC4J with struts and using the EditAction and UpdateAction classes provided by BC4J.
When i want to create a new row in the database the documentation asks me to call EditAction's create() method and then UpdateAction's execute() method to do it. But even when i just call UpdateAction's execute() method I am able to create a new row. So WHY should I call EditAction's create() method ?????

Answer 1

EditAction's create() method is something you would call in the action before rendering the empty form for the user to fill in.
It creates a row, and then marks the row as having STATUS_INITIALIZED using the Row.setNewRowState(Row.STATUS_INITIALIZED) call.
By setting the row to STATUS_INITIALIZED, this makes BC4J "forget" that it's a new row that needs to be inserted. In effect, it makes that new row a throwaway row used only for the purpose of rendering the blank form. An important reason you would want to do things this way is to pickup entity-level default values in the attributes of the new row.
For example, in the toy store demo, why is it that when you register as a new user the "Country" poplist defaults to "United States" ? (it's not the first entry in the list).
The answer is that, since the EditAction (or in this case my custom subclass of that) creates the blank row, the fact that the "toystore.model.businessobjects.Account" entity object declares that its Country attribute has a default value of "US" makes the blank row created in the "toystore.model.dataaccess.Accounts" view object have a default value of "US", and that default value in the blank row causes the <jbo:InputSelect> tag that renders the poplist to mark the corresponding "United States" option in the list as currently selected (as it's the display string associated in the poplist with the value "US").