Helpful layer in oracle application

When developing with the Oracle eBusiness Suite, there are situations where Developers can use "hooks" in standard Applications code to insert or redirect to custom code. Oracle Applications provide some helpful layers of abstraction to make life easier for customization. Where possible it is nice for this to be done using a supported method. If a true blue customization is required, then its best to try to preserve the existing code so that any future upgrades are more likely to break your custom code by reverting to standard code, plus if you use a "hook" to independent code it is easier to maintain and upgrade the custom code. I regularly use a "copy and modify" approach to Apps Development where I use hooks to call the new code.

• Concurrent Program Executable. Where an concurrent program is automatically submitted from a form or another concurrent process, e.g. "Print Pack Slip" in Oracle Shipping actions, as long as parameter requirements are the same, then a quick an easy method to code your own report is:
  1).Create a new executable registered under your custom application, e.g. XMODS_WSHRDPAK
  2).Query the called concurrent program and update the executable to your custom executable,e.g. Query WSHRDPAK and replace executable with XMODS_WSHRDPAK
• Personalization - Forms and Framework (OAF) plus CUSTOM.pll. Forms PL/SQL Library. Personalization has provided functionality to cover a lot of the customizations traditionally coded to CUSTOM.pll, but both Personalization and CUSTOM.pll provide a number of hooks into the front end logic.
• Database Triggers. Triggers on tables used carefully can provide hooks where all other methods don't dare to tread. Of course watch out for the exception and try to avoid putting triggers on fnd_concurrent_requests!
• Menu. Provides a prominent method to call new Forms, while potentially hiding behind the same prompt, Reports, Discoverer Workbooks, external links/URLs, etc. Gives the ability to save in the "Favourites" list. If you need to customize a standard form, copy it and create a new menu entry where possible.
• Unix Softlink. An alternative to the concurrent program executable hook.
  1). Backup an existing standard Oracle file.
  2). Remove the existing standard Oracle file.
  3). Replace with a softlink to a file under you custom application code "top" directory
• Workflow. Workflow customizations are "allowed" and a method I use here is to take a standard function call in workflow, copy and modify the underlying package, then change the function call in workflow to the custom function. E.g. AP Remittance Advice workflow (APPEWF) has "Get Check Info" function calling AP_PAYMENT_EVENT_WF_PKG.get_check_info. Copy AP_PAYMENT_EVENT_WF_PKG to XMODS_AP_PAYMENT_EVENT_WF_PKG and change function in workflow function "Get Check Info"
• Printer Driver. Whenever concurrent request file post processing is required, e.g. to FTP or email a file - printer drivers provide an excellent way to perform post processing. Create a new printer driver with the appropriate command. Remember to restart the concurrent manager to pickup updates to print drivers.
• Business Events. Not a widely used mechanism, but provides supported hooks into key events such as Payment Confirmations (AP Payment event).

New to OA Framework

OAF stands for Oracle Applications Framework and is a MVC architecture based J2EE framework customized for use in Oracle Applications development. It is tailor made for use in the development, customization of Oracle Apps pages and any custom application development to be hosted, integrated in Oracle Apps. OAF provides classes for all the standard web widgets seen on the Self Service pages like Text field, List of Values, Table, HGrid, Buttons etc. You can get that detail in the OAF Dev guide.
Only choice of tool to work with OAF is Jdeveloper with OA Extension. There is no OA extension /plugin available for any other IDE. This is another factor where people keep getting confused. Jdeveloper is a generic Java IDE but the one without the OA extension can't be used for OAF development. OA extension is what provides the required OA libraries and enables OA based Workspace, Project creation.
OAF is the only option for any Oracle Apps related development. Release 11i and recently launched Release 12 version of Oracle Apps is based on OAF. For look & feel and business logic changes to Oracle provided seeded Self Service pages, one can make use of Extension and Personalization features of OAF. Modifications done following the Extension and Personalization guidelines are upgrade and patch safe. Any direct modification made to seeded code will be overwritten during the patching.
If You are going to start work in OA Framework,

1). The First thing you should khow which patch is suitable for your Orcale application release.
2). Once you get the patch number of OA Extension, Download it from the metalink & just extract that zip file into your machine.

a). Then you have to configure the JDEV_USER_HOME Environment Variable, Please follow these setup to configure this:
- Go to your desktop and select My Computer, right-click and select Properties.
- On the System Properties dialog, select the Advanced tab.
- On the Advanced page, select the Environment Variables button.
- On the Environment Variables dialog, select the New button from the User variables for box.
- On the New User Variable dialog, enter JDEV_USER_HOME in the Variable Name field. Set the Variable Value field to :\jdevhome\jdev where is the drive where you installed the JDeveloper OA Extension zip file. For example: c:\jdevhome\jdev. - Select OK in each of the dialogs you opened to save the new user environment variable.

b). Obtaining a Database Connection File
- Obtain the FND database connection (.dbc) file from the system administrator who installed the OA Framework database where you want to do your development. Place this file in the \dbc_files\secure directory.

Then start your Jdeveloper and start working in OA Framework.