Normally, the Network Configuration Assistant (NETCA) is started at the end of the installation process; however, if NETCA fails or you exit before completing, the and the other NETCA created files are not necessary for connecting to the database locally from the server.
They are just for client access, so it is possible for the database to be created properly and the files not exist.
If you are doing something like enabling dead connection detection on a server by setting , for example, it probably makes sense to reboot the server to make sure that the setting applies to all connections rather than just new connections-- if you're trying to debug why a particular dead connection is still hanging around, knowing that the server was restarted and that you're not looking at some artifact of a connection that was opened prior to the setting being made would generally be helpful.
The steps mentioned by Jason are very good and should work.
There is a little twist with SQL Developer, though.
It caches the connection specifications (host, service name, port) the first time it reads the file.
Anytime you change Oracle's or files, does the system require a reboot?
In my instance, I only have the Oracle client installed on the machine I'm referring to, but out of curiosity what would it mean for an Oracle server installation? A change shouldn't require a reboot but some applications will read and parse the at startup to be able to present a drop-down list of servers to the user, for example, and will cache whatever was read when the application started up rather than re-reading the file.