It is not possible to get authorization code behind a proxy that requires authentication

I am developing an application that integrates with a Authentication service in the internet, but the network is behind a reverse proxy with authentication. I tried to set the authentication on java settings: -Dhttps.proxyHost=host -Dhttps.proxyPort=8080 -Dhttps.proxyUser=username -Dhttps.proxyPassword=password , with default Authenticator. But nothing works.