Jakarta EE
Java 2 Platform, Enterprise Edition or J2EE is a Standard for developing distributed Multi-tier architecture applications, based on modular components. The standard uses several technologies, including JDBC and CORBA, and extends their functionality with Enterprise Java Beans, Java Servlets, Java Server Pages and XML technologies. This allows the developer to create an Enterprise Application that is portable between platforms and scalable, while integrating with several legacy technologies.
General APIs
The J2EE APIs includes several technologies that extend the functionality of the base J2SE APIs. Some of these are:
javax.ejb.*
The Enterprise Java Beans API defines a set of APIs that a distributed object container will support in order to provide persistence, remote communication (using RMI), concurrency control, and access control for distributed objects.
javax.servlet
The Servlets API defines a set of APIs between a web container and a servlet that is responsible for processing requests and issuing responses.
javax.servlet.jsp
The javax.servlet.jsp and javax.servlet.jsp.tagext packages define the JavaServer Pages API.
javax.naming
The javax.naming, javax.naming.directory, javax.naming.event, javax.naming.ldap and javax.naming.spi packages define the Java Naming and Directory Interface API.
java.sql, javax.sql
The java.sql and javax.sql packages define the Java Database Connectivity (JDBC) API
java.transaction.*
These packages define the Java Transaction API (JTA)
javax.xml.*
These packages define the JAXP API
javax.jms.*
These packages define the Java Message Service (JMS) API
Low cost development
One of the benefits of J2EE as a platform is that it is possible to get started with little, or no, expenditure. The J2EE implementation from Sun can be downloaded for free, and there are a great many open source tools available to extend the platform or to simplify development.
Examples of third party open source Java development tools include:
- The Eclipse platform, a Java based integrated development environment
- Jakarta Tomcat, a Servlet/JSP web container
- Jakarta JMeter, a load testing tool for web servers
- Apache Ant, an automated build tool
- JUnit, a framework for automating unit tests
- Jasper Reports, a report writer
- JBoss
- Geronimo
- JOnAS
- Novell exteNd
- Jetty
External links
- Sun's J2EE page - official documentation
- TheServerSide.com - popular discussion site for J2EE developers