J2EE, or in the newest versions of Java Platform, Enterprise Edition or just Java EE, is a JAVA platform, which is intended for the development and operation of the business information systems and applications. The basis of this platform is SE platform.
Individual parts of platforms are given by the partial specifications, which are created by multi-company cooperation within i. e. Java Community Process (JCP). Any change request is realized within the Java Specification Request (JSR). These requirements are subsequently approved by the corresponding committee JCP and in a case of positive expression is put together a work group, which works on a relevant specification. The specification itself goes through specific fazes and approvals, which are within the given JCP defined. In committees and work groups work representatives of several companies. The output is then a document with specification, eventually JAVA code, which defines relevant API. If the specification is approved, it is necessary to create the reference implementation of the specification and subsequently is performed set of compatibility tests.
Platform JAVA EE consists of these parts:
JAVA EE platform application is developed on the base of API and other fragments, which are defined within individual specifications. These applications use application sever (AS) as runtime environment. These app servers are supplied by different suppliers, and application should be, according to the theory, operable on any of them, which implement given version of specification. That is called concept of portability. Most of application servers complete part of the features beyond the specification, therefore the applications become non-transferable, if they use these features.
It is necessary, for the application server to be formally marked as JAVA EE compatible, to go through the complete set of compatibility tests in the Sun Microsystems company. Realization of these tests bounds to themselves political problems, that’s why exist servers, which meet the specifications, but don’t have official marking. There also exist application servers, which support only part of JAVA EE platform.
Sun Microsystems created first specification J2EE in 1999-2000. From the version J2EE is the development within JCP.
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