The better your standards—and the better they are adhered to—the easier your code will be to develop and maintain. You can use some or all of the following standards and add your own code. Whenever JDeveloper automatically generates names for things, consider if these are good enough—write a naming standard that deviates from the standard JDeveloper's way only if you feel that the rule has significant benefit.
Your standards should be easily available to everyone on the project in a Wiki or shared document.
This section lays out a proposal for naming the various elements of your ADF application. Oracle has also produced an official naming guidelines document that you can find at http://www.oracle.com/technetwork/developer-tools/adf/learnmore/adf-naming-layout-guidelines-v2-00-1904828.pdf.