About OC4J Deployment Application Directory Structure

Whenever you deploy an application, OC4J automatically generates the OC4J-specific XML files with the default elements. JDeveloper lets you edit these files or add to the existing XML files in JDeveloper. It copies the XML files to your original development directory for the application and changes it in this location. If you change the XML file within the deployed location, OC4J simply overwrites these changes when the application is deployed again.

For all OC4J-specific XML files (file names begin with orion ), you can add these files within the recommended development structure as shown below:

META-INF
- application.xml
- orion-application.xml
ejb
- EJB classes (my.ejb.class maps to /my/ejb/class)
- META-INF
  - ejb-jar.xml
  - orion-ejb-jar.xml
web
- index.html
- JSP pages
- WEB-INF
  - web.xml
  - orion-web.xml
  - classes
    - Servlet classes
client
- Client classes
- META-INF
  - application-client.xml
  - orion-application-client.xml
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You can provide all application XML files in either of the following:

Within the application directory as specified by J2EE. This is recommended because it keeps the global and default configuration files separate from the application-specific configuration files.
JDeveloper recognizes the deployment descriptor file in META-INF/application-client.xml, found in the first entry of the source path. Any other names and locations for application-client.xml file will be ignored.
Within the config directory with all of the OC4J server XML files. Refer to the Oracle Application Server Containers for J2EE User's Guide provided with the Oracle Application Server documentation library for information on the deployed location of the application files including these files.