Separating the RO Client and the ROApp Server - Programming GPS and OpenStreetMap Applications with Java - page 137

RemoteObjectsApplication login ( RemoteObject client )
throws RemoteException;

Now, the method returns the RemoteObjectsApplication interface defining
the actual interaction with the scenario. Note that the interface could also
be retrieved by casting the RemoteServer . Nevertheless, the client should
apply the formal identification and login procedure for an explicit server
authorization.
The two interfaces indicate a handshake in two phases. First, the client
looks up the remote server to get time and space and identifies itself, and
then the server adds its reference to the ROApp scenario. Note that the
client's stub is not bound (published) to a registry, since it can be passed
to the server programmatically.

Connecting via lookup on a registry is

only needed once. Finally, the client and server can inspect each other

asynchronously.

10.2.3 RO-ROApp Sequence Diagram

The sequence diagram below provides a good overview of the client-server
dialog:

server machine any machine

RealObjectsApplication Registry

---------------------- --------

1. getRegistry <-- host + port client machine

RealObjectClient

2. new ROApp --> export ----------------

3. bindRemoteObject --> SERVERNAME <-- 4. Naming.lookup
| |
Registry no longer needed |
|
<--- reference --- 5. (RemoteServer)

new GPSinfo ---- copy --> 6. getGPSinfo()

7. new ROClient(GPSinfo)

8. export new RemoteClient
|
(RemoteObjectClient) --- reference ---> login ( client )
<-- reference -- (RemoteObjectsApplication)

movingObjects.add( client ) replayGPStrace

<--- interact --->