URLyBird - Network Server

[Nicolas Stern]

Hi everybody

I have the following questions relative to the Network Server part of my assignement. I don't have a lot of experience with RMI, so I apologize if the questions seem too trivial.

1. JRMPM
y requirement state: "You must use RMI over JRMP (do not use IIOP)"
Is this provided, if the client calls the Server in the following way:

    
...
try {
Registry reg = LocateRegistry.getRegistry(PORT_NUMBER);
myNetworkDataSource  = (NetworkDataSource)reg.lookup(SERVICE_NAME);
} catch (...)

The NetworkDataSource is the interface for the remote methods. The Implementing Class had been instanciated with

    
registry.bind(SERVICE_NAME)

2. Security Manager
My assignment states "you must not require the installation of a security manager"
Most of the tutorials sample applications instanciate programatically a SecurityManager instance (this is not necessary)

    
if (System.getSecurityManager() == null) {
System.setSecurityManager(new SecurityManager());
}

Is the security manager of the assignement statement the same as the one in the code snippet ?
3. Connections
In a network mode, I can observe a new connection on a separate port for every client call. After a while, they disappear. Do I have to explicitely open and close every connection, or can I rely on the RMI environment for cleaning up. Nothing is mentionned in my assignement. (I come from the Database world and am perhaps a bit anxious about "not released resource" :-)

Thanks for any input - cheers

[Andrew Monkhouse]

Hi Nicolas,

Correct.

Unless you specifically request IIOP you are going to end up using JRMP.

Yes, that is the security manager that you are not allowed to use.

If you start the RMI Registry programatically you will not need to use a security manager.

When disconnecting a client it is always a good idea to explicitly close your connection to the server. If you feel like being really good you could also call the garbage collector which will provide a hint that the distributed garbage collector should run, but this is not essential.

However you do not need to explicitly create or clear connections while you are in the middle of processing.Regards, Andrew