J2EE makes Java a fully-fledged server-side development platform.
What is JAVA/J2EE?
Java is a popular programming language, created in 1995.
It is owned by Oracle, and more than 3 billion devices run Java.
It is used for:
FEATURES OF JAVA/J2EE
Unlike many other programming languages including C and C++, when Java is compiled, it is not compiled into platform specific machine, rather into platform-independent byte code. This byte code is distributed over the web and interpreted by the Virtual Machine (JVM) on whichever platform it is being run on.
The purpose of a transaction is to ensure that data is updated in an all-or-nothing fashion in order to preserve data integrity. The transaction service provides transactional resource managers for the JDBC API, the JMS API, and resource adapters (connector modules). In the Sun ONE Application Server, you can configure transactions and reference them using the JNDI API.
The JavaMail API allows J2EE applications to create, send, receive, and read mail messages. The JavaMail API includes support for the IMAP4, POP3, and SMTP mail protocols. JavaMail sessions are made available through the JNDI API.
Database Connectivity (JDBC)
The standard way to connect to a database from a J2EE application or module is through a JDBC driver. Sun ONE Application Server supports the core JDBC 3.0 API and the JDBC 2.0 extensions and works with a wide range of JDBC Compliant™ drivers. A JDBC resource associates a JDBC driver and database to a JNDI name that applications and modules can reference.
Java Message Service (JMS)
The JMS API provides a common way for J2EE applications and modules to create, send, receive, and read messages in a distributed environment. The fully integrated JMS provider for Sun ONE Application Server is the Sun™ Open Net Environment (Sun ONE) Message Queue software. JMS queues, topics, and message destinations are made available through the JNDI API.