Storing Java objects in the Apache directory server, part 1th

Introduction: This two-part series describes the steps to save a Java™ object in the Apache directory Server (ApacheDS). In the 1th part, author Bilal Siddiqui introduces ApacheDS and provides an overview of the ApacheDS core architecture. Because ApacheDS is used primarily as an LDAP server for storing Java objects, Bilal provides a quick overview of LDAP concepts and terminology. He also describes how to use Jxplorer to view LDAP schema components, such as attribute types and object classes, and also describes how to enter data Objects in ApacheDS. The end of the article outlines the serialization of Java objects and remote method calls, and uses them to save Java objects in ApacheDS, preparing for a more practical approach in part 2nd.

The Apache directory server is an open source, java-based implementation of numerous Internet protocols. The core of ApacheDS is the directory service, which can save data and search for different types of data. The implementation of the Protocol works at the top level of the directory server and provides Internet services related to data storage, search, and retrieval.

The most important feature of ApacheDS may be the ability to expose directory services using different protocols. This means that the data of the application (including Run-time Java objects) can be stored in ApacheDS, and different clients can use different protocols to exploit the data. The most important protocol implemented by ApacheDS is the Lightweight Directory Access Protocol (LDAP). ApacheDS acts as an LDAP server, listens for requests, coordinates with internal core directory services, and responds to LDAP requests.

In this two-part series, I'll introduce the core ApacheDS architecture and describe all the steps to save the Run-time Java object in ApacheDS. Since my focus on ApacheDS is almost entirely in its implementation as an LDAP server, the 1th part of this series focuses on LDAP features and terminology. But before entering this section, I want to introduce the extensible architecture of ApacheDS, and explain how to use it to insert new protocol implementations and Internet services into ApacheDS. An understanding of how the ApacheDS Core directory service works helps to understand the way it provides LDAP functionality.

To keep up with the discussion of this article, you need to download and install ApacheDS and jxplorer. You may also want to download the full source code for the article to use.

Directory Services in the ApacheDS

A directory service is an application that stores and organizes data. The directory service processes data that does not require frequent updates, such as the user's personal data (such as name, address, telephone number), or the production capacity of the workshop (such as the number of installed devices, model numbers, and production capacity). In part 2nd of this series, you will describe a sample application that consolidates both types of data. Now, I focus on the way ApacheDS provides directory services.

ApacheDS Implement JNDI

As you can see in Figure 1, ApacheDS implements the Java name and directory interface (JNDI) wrapper for its core directory service. JNDI is a Java interface that defines methods for performing directory operations, such as saving data in a directory and searching for saved data. JNDI is an integral part of the Java 2 Enterprise Edition (EE) and Java 2 Standard Edition (J2SE). Where J2SE contains only client-side Jndi support, and the Java container typically contains a server-based jndi implementation. The Java EE container can use its directory service through the ApacheDS JNDI wrapper, as shown in Figure 1:

Figure 1. ApacheDS works in Java container