Initial context support
All naming operations begin with obtaining an initial context. We can view the initial context as a starting point in the namespace. Use the initial context to perform naming operations, such as looking up and binding objects in the namespace.
Initial contexts registered with the ORB as initial references
The root contexts listed in the following table 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 namespace lookups. The keys for these roots as recognized by the ORB are shown in the following table:
Server Root NameServiceServerRoot Cell Persistent Root NameServiceCellPersistentRoot Cell Root NameServiceCellRoot, NameService Node Root NameServiceNodeRoot Applications Root NameServiceApplicationsRoot 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.
We 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.
Default initial contexts
The default initial context depends on the type of client. Different categories of clients and the corresponding default initial context follow.
- WebSphere Application Server JNDI interface implementation
- The JNDI interface is used by EJB applications to perform namespace lookups. WebSphere Application Server clients by default use the WAS 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.
- Other JNDI implementation
- Some applications can perform namespace lookups with a non-product 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.
- CORBA
- 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.
Related concepts
Naming Namespace logical view
Related tasks
Use naming Develop applications that use JNDI Develop applications that use CosNaming (CORBA Naming interface)
Example: Getting the default initial context Example: Getting an initial context by setting the provider URL property Example: Getting an initial context with CosNaming