When you are working with configuration files, POM file, you can see these files appear in ‘Resources’ folder. But sometimes though the files present in file directory they won’t show up in the JDeveloper. To get those appear in Jdev follow below given instructions.
Right click on Project -> Project Properties -> Project Source Paths -> Resources -> click on Add -> select the project -> Ok
After adding you can see Resources folder appear in Jdev as shown below.