Two-tier application development architecture was most commonly used in the past to develop client/server software applications that required a central database server to be accessed by one or more client machines. Two-tier application architecture had its limitations when it came to the maintenance and installation of upgrade patches for individual clients. The higher the number of client machines, the more challenging maintenance became. Then along came multi-tiered application architecture, which was designed to tackle the challenges of two-tiered architecture. Multi-tiered architecture is now at the heart of distributed applications.
J2EE is a distributed application development technology created by Sun Microsystems to develop software applications based on multi-tier architecture. J2EE is designed to avoid the need to write thousands of lines of low-level programming code, which is now handled by the application server. This enables the developers to focus more on writing high-level code that directly relates to the business logic for which the application is being developed. Hence, the resulting business applications are more robust, error free, less time consuming and less complex to develop.
J2EE distributed application development requires the use of the following tools and technologies. A thorough understanding of these is a must for Java application development using J2EE. A brief description of them and their application follows.
JSP is a tool to integrate Java code with HTML for the purpose of developing dynamic web pages and to retrieve and insert and manipulate information contained in the database server.
EJB is defined by Sun Microsystems as, "The Enterprise JavaBeans architecture is a component architecture for developing and deployment of component-based distributed applications. Applications written using the Enterprise JavaBeans are scalable, transactional, and multi-user secure. These applications may be written once, and then deployed on any server platform that supports the Enterprise JavaBeans specification."
JDBC, as the name suggests, is a J2EE tool designed to provide easy connection with a database server so the Java program can insert, retrieve, delete or update data in the database.
RMI is a J2EE tool to invoke Java methods on remote objects.
JNDI is an interface provided in J2EE that enables Java applications to access naming and directory applications of an organization, such as Active Directory or LDAP
IDL is a tool in J2EE to communicate with COBRA. COBRA is Common Object Request Broker Architecture, which is a standard architecture designed to integrate different software components written in different programming languages.
JSs are components that enable server-side application development in Java.
No Related Indexes