A URL task flow is bounded task flow that is deployed as
a stand-alone Java EE application on a remote server with its URL Invoke property set to url-invoke-allowed. The URL task flow
is accessed either from a direct browser GET request or, when called from
another ADF application, through the task flow call activity.
For more information about how to invoke URL task flows from
a task flow call activity see chapter 15.6.4
How to Call a Bounded Task Flow Using a URL of the Oracle Fusion Middleware
Fusion Developer's Guide for Oracle Application Development Framework at
Compared to WRSP portlets, URL task flows in Oracle
JDeveloper 11g R1 and R2 have a functional limitation in that they cannot be
embedded as a region on a page but require the calling ADF application to
navigate off to another application and page. The difference between a URL
task flow call using the task flow call activity and a simple redirect to a
remote Java EE application is that the URL task flow has a state token
attached that allows to restore the state of the calling application upon task
A use case for a URL task flow call activity is a "yellow
page lookup" scenario in which different ADF applications use an URL task flow to lookup people, products or similar to return a selected value to
the calling application.
Note that URL task flow calls need to be performed from a bounded or unbounded top level task
flow of the calling application. If called from a region (using the parent call
activity) in a page, the region state is not recovered upon task flow return.
ADF developers recently have identified URL task flows
as an architecture pattern to partition their ADF applications into independently
deployed Java EE applications. While this sounds like a desirable use of the URL task flow feature, it is not possible to achieve for as long as URL
task flows don't render as an ADF region.