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Hi Can you let me know if my reasoning is correct ? Thanx I tried to replace my rmiregistry bound RemoteDataImpl object with a "Connection Factory", now I'm not sure I see things correct... My original design was : db package ---------- - all classes provided by Sun - DataInterface extends Remote contains all public Data methods throwing base class Exceptions - LockManager nested within Data Class - Data implements DataInterface server package -------------- - RemoteDataImpl extends UnicastRemoteObject implements DataInterface : methods throw RemoteException besides DatabaseExceptions and IOExceptions RemoteDataImpl wraps a Data object and delegates all method calls - Server : binds RemoteDataImpl to RMIRegistry client package -------------- - LocalDataImpl implements DataInterface. Methods throw exceptions stated in Data methods,no RemoteException. LocalDataImpl also wraps a Data object and also delegates all method calls to this Data object - DataProxy implements DataInterface, methods throw base class Exceptions. Has 2 ctors : 1 for local, 1 for remote. Wraps LocalDataImpl or RemoteDataImpl depending on ctor of choice As you can see I even used a LockManager in local mode because it was accessed via Data object Also, changing the lock/unlock signatures was necessary
When I want to use a Connection Factory I have to achieve :
DataInterface no longer extends Remote nor throws base class Exceptions, just throwing DatabaseExc and IOExc. RemoteDataImpl (this is the same as your Connection Object, right ??!!) no longer throws RemoteExceptions. It still wraps a Data object, but one initialized by the connection factory (enters via ctor) (**) - delegates lock/unlock to a Singleton LockManager's lock/unlock - implements serializable RMIRegistry bound ConnectionFactory returning new RemoteDataImpl objects, provided with a reference to the Data object(**) Is this the correct way to do it ?? Thanks !!!
Actually in mine, the ConnectionFactory and the "Connection" objects it returns are separate classes. The ConnectionFactory only has a constructor, which calls super() Then the main which: 1. makes an instance of itself 2. creates the registry 3. makes a Data instance 4. Binds the factory into the registion Then there is the getConnection method which creates an instance of your remote implementation, passing the Data instance to it constructor. and then returns the remote implementation to the client. Mark [ April 12, 2002: Message edited by: Mark Spritzler ]