Use naming
Overview
Naming is used by clients of WAS applications most commonly to obtain references to objects related to those applications, such as EJB homes.
The Naming service is based on JNDI 1.2.1 Specification and the Object Management Group (OMG) Interoperable Naming (CosNaming) specifications:
- Naming Service Specification
- Interoperable Naming Service revised chapters
- Common Object Request Broker: Architecture and Specification (CORBA)
Procedure
- Develop your application using either JNDI or CORBA CosNaming interfaces. Use these interfaces to look up server application objects that are bound into the name space and obtain references to them. Most Java developers use the JNDI interface. However, the CORBA CosNaming interface is also available for performing Naming operations on WAS name servers or other CosNaming name servers.
- Assemble your application using an application assembly tool. Application assembly is a packaging and configuration step that is a prerequisite to application deployment. If the application you are assembling is a client to an application running in another process, you should qualify the jndiName values in the deployment descriptors for the objects related to the other application. Otherwise, you may need to override the names with qualified names during application deployment. If the objects have fixed qualified names configured for them, you should use them so that the jndiName values do not depend on the other application's location within the topology of the cell.
- Deploy your application.
Put your assembled application onto the application server. If the application you are assembling is a client to an application running in another server process, be sure to qualify the jndiName values for the other application's server objects if they are not already qualified. For more information on qualified names, refer to Lookup names support in deployment descriptors and thin clients.
- Configure name space bindings. This step is necessary in these cases:
- Your deployed application is to be accessed by legacy client applications running on previous versions of WebSphere Application Server. In this case, configure additional name bindings for application objects relative to the default initial context for legacy clients. (V5 clients have a different initial context from legacy clients.)
- The application requires qualified name bindings for such reasons as:
- It will be accessed by J2EE client applications or server applications running in another server process.
- It will be accessed by thin client applications.
In this case, one can configure name bindings as additional bindings for application objects. The qualified names for the configured bindings are fixed, meaning they do not contain elements of the cell topology that can change if the application is moved to another server. Objects as bound into the name space by the system can always be qualified with a topology-based name. You must explicitly configure a name binding to use as a fixed qualified name.
For more information on qualified names, refer to Lookup names support in deployment descriptors and thin clients. For more information on configured name bindings, refer to Configured name bindings.
- Troubleshoot any problems that develop. If a Naming operation is failing and we need to verify whether certain name bindings exist, use the dumpNameSpace tool to generate a dump of the name space.
See also
Naming
Name space logical view
Initial context support
Lookup names support in deployment descriptors and thin clients
JNDI support in WebSphere Application Server
Developing applications that use JNDI
Developing applications that use CosNaming (CORBA Naming interface)
Configured name bindings
Name space federation
Name space bindings
Configuring and viewing name space bindings
Configuring name servers
Troubleshooting name space problems
Naming and directories: Resources for learning