31-05-2012, 01:16 PM
Java EE (Enterprise Edition )
What_is_JavaEE.ppt (Size: 1.52 MB / Downloads: 248)
Using the Java™ Platform, Enterprise Edition (Java EE) architecture, you can build distributed Web and enterprise applications. This architecture helps you focus on presentation and application issues, rather than on systems issues.
Java Write Once, run anywhere (WORA)
Enterprise application strategy:
- Application & h/w both have a useful life
- Through away Philosophy works well for applications that services small group of users
Ex: Departmental needs
Goals of Enterprise Application
Enterprise application is practically any application used by more than one person
Ex:
1.Concurrently used by more than a handful of users
2. User distributed resources such as DBMS that are shared with other application
3. Delegates responsibility to perform functionality among distributed objects that are located at different places
4. Uses web services architecture & J2EE technology to link together component
Java EE Components
Following are the Java EE components:
Application clients and applets tht run on the client
Java Servlet, JavaServer Faces, and JavaServer PagesTM (JSPTM) technology components are web components
Enterprise JavaBeansTM (EJBTM) components (enterprise beans) are business components that run on the server.
The difference between Java EE components and “standard” Java classes is that Java EE components are assembled into a Java EE application, are verified to be well formed and in compliance with the Java EE specification, and are deployed to production, where they are run and managed by the Java EE server.
Web Components
Java EE web components are either servlets or pages created using JSP technology (JSP pages) and/or JavaServer Faces technology
Servlets are Java programming language classes that dynamically process requests and construct responses
JSP pages are text-based documents that execute as servlets but allow a more natural approach to creating static content.
JavaServer Faces technology builds on servlets and JSP technology and provides a user interface component framework for web applications.
Business Components
an enterprise bean receives data from client programs, processes it (if necessary), and sends it to the enterprise information system tier for storage. An enterprise bean also retrieves data from storage, processes it (if necessary), and sends it back to the client program.