All naming operations begin with obtaining an initial context. You can view the initial context as a starting point in the name space. Use the initial context to perform naming operations, such as looking up and binding objects in the name space.
The server root, cell persistent root, cell root, and node root are registered with the name server's ORB and can be used as an initial context. An initial context is used by CORBA and enterprise bean applications as a starting point for name space lookups. The keys for these roots as recognized by the ORB are shown in the following table:
Root Context | Initial Reference Key |
Server Root | NameServiceServerRoot |
Cell Persistent Root | NameServiceCellPersistentRoot |
Cell Root | NameServiceCellRoot, NameService |
Node Root | NameServiceNodeRoot |
A server root initial context is the server root context for the specific server you are accessing. Similarly, a node root initial context is the node root for the server being accessed.
You can use the previously mentioned keys in CORBA INS object URLs (corbaloc and corbaname) and as an argument to an ORB resolve_initial_references call. For examples, see CORBA and JNDI programming examples, which show how to get an initial context.
The default initial context depends on the type of client. Different categories of clients and the corresponding default initial context follow.
The JNDI interface is used by EJB applications to perform name space lookups. WebSphere Application Server clients by default use the WebSphere Application Server CosNaming JNDI plug-in implementation. The default initial context for clients of this type is the server root of the server specified by the provider URL. For more details, refer to the JNDI programming examples on getting initial contexts.
Some applications can perform name space lookups with a non-WebSphere Application Server CosNaming JNDI plug-in implementation. Assuming the key NameService is used to obtain the initial context, the default initial context for clients of this type is the cell root.
The standard CORBA client obtains an initial org.omg.CosNaming.NamingContext reference with the key NameService. The initial context in this case is the cell root.