Use Case for ADF BC With No Database Connection

There is very good sample application from Steve Muench - #147 ADFBC Application With No Database Connection (not yet documented). I was using it to implement recent request from the project, its why I would like to document it. We had a discussion with SOA developers and they were wondering if its possible to run ADF BC application, without DB access. This is quite common use case in SOA projects, there is no direct access to DB and we need to consume data through Web Service layer, as for example. Yes its possible and I see quite strong advantage of ADF BC, even when working with non DB data sources - its easy to centralize data access through programmatic VO's, its fast to expose programmatic VO through Data Control and finally is easy to capture user data input, use out of the box functions to process user data (getting current row from VO, iterating over row set, creating new rows, deleting rows, etc.). This can be as alternative for Web Service Data Control.

Sample application - ADFBCNoDatabaseWSApp.zip use case is described in this diagram:

ADF BC application is disabled from creating database connection, instead it contains programmatic VO to retrieve data from alternate data source.

I would recommend to check Steve Muench sample #147 (see link above), for this use case I took original code and migrated it to JDev 11g R2:

If you want to disable database access for ADF BC application, you will need to update bc4j.xcfg with proper entries. I would recommend to update this file from outside, not from JDeveloper - otherwise you may experience errors - seems like JDeveloper IDE is constantly scanning changes from bc4j.xcfg. Make sure to update bc4j.xcfg as from sample application, for example RequiresConnection=false and other settings:

Default Connection Strategy is extended to disable database connection:

Application Pool is disabled to perform passivation:

Handle Commit and Handle Rollback methods are disabled:

We are done with extending framework. Now I can describe simple use case - programmatic VO to retrieve user roles from WebLogic security provider (based on my previous post). Programmatic VO is reading data from WebLogic security provider:

View Object doesn't have any SQL statement, obviously it retrieves data from non database source:

When building ViewController, we can use regular Data Control - same as we would have from standard ADF BC:

Data is rendered successfully on ADF UI:

In this case, application runs independently of database and we still can use all powerful ADF BC data processing features.