First run:
$ mvn compile
You can run the examples afterwards like this:
$ mvn exec:java@run-reader-examples -Daccess_token=MY_ACCESS_TOKEN
$ mvn exec:java@run-publisher-examples -Daccess_token=MY_ACCESS_TOKEN
$ mvn exec:java@run-login-example -Dapp_id=APP_ID -Dapp_secret=APP_SECRET
Instructions for getting an OAuth access token are available on RestFB. Or simply take one from Facebook Graph API Explorer. You need maven (>3.3.1) to be installed on your system.