question: public static void checkConnection ( @ Nonnull String hostname , @ Nonnull String username , @ Nonnull String password , @ Nonnull String encryption , int port , boolean disableCertificateChecking ) throws MessagingException { Properties props = createProperties ( hostname , port , encryption , disableCertificateChecking ) ; Session session = Session . getInstance ( props , null ) ; Transport transport = session . getTransport ( "smtp" ) ; transport . connect ( username , password ) ; transport . close ( ) ; }
target:  Check SMTP login credentials