Hemanth,
Forms, Reports, etc. are all compiled in Oracle Apps using the adadmin utilities. The utilities allow you to specify what you want to compile (report, library, etc.), and for what module(s). Once specified, jobs are spawned and assigned to workers to compile. Depending on the speed and number of CPU’s on a server, a full compile for everything can take quite some time.
You can also recompile objects from the command line on the server - the syntax varies depending on what you are compiling.
If you have custom code developed in a previous release of the Applications, the first thing you need to determine is what version of the development tool you are coming from in the old release, and going to in the new one. It might not be as simple as recompiling your custom code if you are making a significant upgrade (say from 10.7 or 11 to 11i). Also keep in mind that the data model can also change, so there is a chance that your code would need to be modified.
Whenever doing an upgrade, I always take an inventory of custom objects and review them to determine if 1) they are still needed (replace with vanilla code if possible!); and 2) if they will require code revisions for the upgrade.
I hope this helps.
Regards,
Michael Siebert
