The Java? 2 Platform, Enterprise Edition (J2EE) provides a standard for developing multitier, enterprise services.
The economy and technology of today have intensified the need for faster, more efficient, and larger-scale information management solutions. The J2EE specification satisfies these challenges by providing a programming model that improves development productivity, standardizes the platform for hosting enterprise applications, and ensures portability of developed applications with an extensive test suite.
J2EE architecture supports component-based development of multi-tier enterprise applications. A J2EE application system typically includes the following tiers:
1. Client tier: In the client tier, Web components, such as Servlets and JavaServer Pages (JSPs), or standalone Java applications provide a dynamic interface to the middle tier.
2. Middle tier: In the server tier, or middle tier, enterprise beans and Web Services encapsulate reusable, distributable business logic for the application. These server-tier components are contained on a J2EE Application Server, which provides the platform for these components to perform actions and store data.
3. Enterprise data tier: In the data tier, the enterprise's data is stored and persisted, typically in a relational database.
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