THE JAVA 2 ENTERPRISE EDITION
The Java 2 Platform, Enterprise Edition (J2EE), has rapidly established a new
programming model for developing distributed applications. This model is based on
well-defined components that can automatically take advantage of sophisticated
platform services. These components can be developed according to standard
guidelines, combined into applications, deployed on a variety of compatible server
products, and reused for maximum programmer productivity. This model is intended to
both standardize and simplify the kind of distributed applications required for
today's networked information economy.
J2EE Platform Benefits
With features designed to expedite the process of developing distributed
applications, the J2EE platform offers several benefits:
� Simplified architecture and development
� Freedom of choice in servers, tools, and components
� Integration with existing information systems
� Scalability to meet demand variations
� Flexible security model
HYPER TEXT MARKUP LANGUAGE
HTML was specifically developed to use along with the Hyper Text Transfer Protocol
(HTTP) to encode documents for display on the World Wide Web.HTML is defined in the
HTML Standard, currently Version 4.0x. HTML standards are recommended by the World
Wide Web Consortium, W3C. W3C also oversees the standardization of technologies
related to the World Wide Web and publishes the HTTP (Hypertext Transfer Protocol)
standards. HTML is initials for Hyper Text Markup Language. HTML is pronounced one
letter at a time as if you are spelling the word HTML. It is not pronounced as "hit
mill" and it is NOT a programming language. HTML cannot be used to write programs
and it cannot control the precise layout of a web page. Web browsers are used to
view HTML documents. Two popular web browsers are the Netscape Navigator 4.x and
the Microsoft Internet Explorer 5.x. Browsers control the layout of a web page
JavaScript:
JavaScript enables you to embed commands in an HTML page. JavaScript is powerful
and simple. HTML provides a good deal of flexibility to page authors, but HTML by
itself is static; after being written, HTML documents can�t interact with the user
other than by presenting hyperlinks. Scripting languages act as the glue that binds
every thing together. JavaScript mainly provides a fairly complete set of built- in
functions and commands, enabling you to perform math calculations, manipulates
strings, play sounds, open new windows and new URLs, and access and verify input to
your web forms.
JavaScript can also set the attributes, or properties, of web page elements and
other objects present in the browser.
This way you can change the behavior of plugs�in or other objects without having to
rewrite them. JavaScript commands
Macromedia Dreamweaver
? Macromedia Dreamweaver2.0 is one of the HTML Editor
? It also includes DHTML effects
? It is used to connect the forms to Servlets
? It is used to Hyperlinks the web pages
? It is used to create Templates
? It is used to attach Sound files and Animation files along with our Source.
The Java Server Pages (JSP):
Java Server Pages � technology is the Java � platform technology for building
applications containing dynamic Web content such as HTML, DHTML, XHTML and XML.
TheJavaServer Pages technology enables the authoring of Web pages that create
dynamic content easily but with maximum power and flexibility.
Advantages:
� Write Once, Run Anywhere � properties
� High quality tool support
� Reuse of components and tag libraries
� Separation of dynamic and static content
� Support for scripting and actions
� Web access layer for N-tier enterprise application architecture(s)
JSP page:
A JSP page is a text-based document that describes how to process a request to
create a response. The description intermixes template data with some dynamic
actions and leverages on the Java Platform.The features in the JSP technology
support a number of different paradigms for authoring of dynamic content. JSP pages
can be used in combination with Servlets, HTTP, HTML, XML, Applets, JavaBeans
components and Enterprise JavaBeans components to implement a broad variety of
application architecture(s) or models.
? Maximum performance and scalability through its unique design with the
Window�s multi-threaded architecture.
? Central and easy-to-use the Graphical User Interface (GUI).
? Automatic authentication of users by the Operating System.
ENTERPRISE JAVABEAN (EJB):
EJB is a standard server side component model for component transaction
monitors. It automatically takes in to account many of the requirements of business
systems-security, resourse pooling,persistence, concurrency and transasction
integrity.
Overall goals
The Enterprise JavaBeans (EJB) architecture has the following goals:
? The Enterprise JavaBeans architecture will be the standard component
architecture for building distributed object-oriented business applications in the
Java programming language. The Enterprise JavaBeans architecture will make it
possible to build distributed applications by combining components developed using
tools from different vendors.
