ODB

The odb example shows how an arbitrary number of Objects can be created by a service. The Reference data used by each Object is stored as part of the IOR. Only the service gets registered with an agent and not individual Objects. This facilitates OODB integration - Can store object keys as part of Object Reference. The BOA will call user defined Activators if the appropriate object is not yet created (The application can then load the object from persistent storage).

• Use string_to_object() and object_to_string()
• Use user defined activators  to create objects in the server

Directory Contents

• db.idl


IDL interface or DB and DBObject.

• Server.java


Use the Service/Activators to create objects, return them and deletes them.

• Creator.java


Calls the DB interface to create 100 objects and stores the "stringified object references" in a file.

•  Client.java 


Reads the "stringified object references"  from the file and makes calls on them. This would have the effect of Activators getting called on the server to create the objects.

Running this example

To run the examples, first make sure that the VisiBroker Smart Agent (osagent executable) is running on your network. Then start the server using the command:

prompt> vbj Server -OAport 12345 &
(start vbj Server -OAport 12345 on Windows)
// Run Server in the background

Note that we specify a particular OAport for the server to start. Next, run the creator:

prompt> vbj Creator

The creator program creates 100 objects, writes the object references to a file and exits.

Kill the server that you started above. Then, restart it with the same OAport number 12345 used above by typing the command:

prompt> vbj Server -OAport 12345 & 
(start vbj Server -OAport 12345 on Windows)
// Run Server in the background

Next, run the client.

prompt> vbj Client

The client reads the object references from the file and calls get_name on them.