Day 4. Using JNDI for Naming Services and Components

In today's lesson, you will learn about JNDI (Java Naming and Directory Interface), one of the commonly used services in any J2EE component-based application. JNDI is a standard interface to naming and directory services for enterprise applications. JNDI also can be used to access heterogeneous naming and directory services from the same application by using the same API. The following sections will explore the concepts of both naming and directory services. Then you will start to learn about the JNDI API and its interfaces and classes to access those services. We will also shed light on how JNDI can be used to look up resources and components as the foundation for other J2EE APIs.

Developers write J2EE components that use JNDI to locate both administrative and declarative objects. In the following days, JNDI will be used in detail with respect to each J2EE service. However, in today's lesson, an understanding of the concepts of JNDI is fundamental to Enterprise JavaBean (EJB) enterprise applications. Clients use the JNDI API to locate EJB components (Days 6, 8, 10, and 11), Java Message Service (JMS) queues and topics (Day 13), and Java Database Connectivity (JDBC) DataSources (Day 9).

• Learn the concepts of naming services

• Learn the concepts of directory services

• Explore the JNDI architecture

• Learn the JNDI API classes and interfaces

• Study the JNDI context and its operations

• Explore how to use the JNDI to support other J2EE services

Before you start, you must download and install an application server, either WebLogic Server or JBoss Server. Appendix A, “WebLogic Application Server 7.0,” explains how to install WebLogic Server. Appendix B, “JBoss Application Server 3.0,” contains the instructions for installing the JBoss Server.