If you don’t want to import your own icons as a resource into ADF you can use the internal ones without having to manually add them to your project.
You can find them by unzipping the adf-richclient-impl jar file from your JDeveloper installation path.
For example on a 11g installation : MW_HOME_INSTALL_PATH\oracle_common\modules\oracle.adf.view_11.1.1\adf-richclient-impl-11.jar
Once unzipped, you’ll find the icons in the “adf/images” folder. (see picture above)
Once you identify the icon you want to use; don’t copy it into your project but reference it like this :