null host identifier (empty string translated to null reference value) //localhost localhost hostname //localhost localhost hostname and port number //localhost:1234 localhost hostname, preceeded with // //localhost localhost hostname and port number, preceeded with // //localhost:1234 protocol and hostname local://localhost protocol, hostname, and port local://localhost:1234 dotted ip for hostname //10.0.0.1 dotted ip for hostname, preceeded with // //10.0.0.1 dotted ip for hostname and port number, preceeded with // //10.0.0.1:1234 protocol and dotted ip for hostname local://10.0.0.1 protocol, dotted ip for hostname, and port local://10.0.0.1:1234 hostname and specificed server name, preceeded with // //localhost/ServerName hostname, port, and specificed server name //localhost:1234/ServerName hostname, port, and specificed server name, preceeded by // //localhost:1234/ServerName protocol, hostname, and specificed server name local://localhost/ServerName protocol, hostname, port, and specificed server name local://localhost:1234/ServerName dotted hostname and specificed server name //10.0.0.1/ServerName dotted hostname and specificed server name, preceeded with // //10.0.0.1/ServerName dotted hostname, port, and specificed server name, preceeded by // //10.0.0.1:1234/ServerName protocol, dotted hostname, and specificed server name local://10.0.0.1/ServerName protocol, dotted hostname, port, and specificed server name local://10.0.0.1:1234/ServerName protocol, hostname, port, and specificed server name, with query local://localhost:1234/ServerName?interval=9876 protocol, dotted hostname, port, and specificed server name, with query local://10.0.0.1:1234/ServerName?interval=9876 protocol, hostname, port, and specificed server name, with fragment local://localhost:1234/ServerName#frag protocol, dotted hostname, port, and specificed server name, with fragment local://10.0.0.1:1234/ServerName#frag protocol, hostname, port, and specificed server name, with query and fragment local://localhost:1234/ServerName?interval=9876#frag protocol, dotted hostname, port, and specificed server name, with query and fragment local://10.0.0.1:1234/ServerName?interval=9876#frag file URI file://localhost special syntax - not a valid URI, but allowed by HostIdentifier rmi://localhost:1234 special syntax - not a valid URI, but allowed by HostIdentifier rmi://10.0.0.1:1234