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“ WEB TECHNOLOGIS “

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ABSTRACT: This paper is explaining the technologies that are used in the world wide web. WWW is distributed system in which all web pages are stored. WWW is a information highway. Inorder to design such a good information highway we need sophisticated technologies. In this paper we are going to present some technologies by using which we can design such a sophisticated web. Web technologies are: Html, Java script, Jsp, Java, Java Beans, VRML, JDBC, Web/Database Interfaces XML DHTML .we will use html to design the web pages, Javascript to do the client side validation, Jsp to process the request that are sent by the client machine using the web browser. web browser is a web client by using which we can sent the request to the web server there is server side program called Jsp which will process the request and return the result to the web browser he will intern present the result to the users. Java is the scripting language for Java script. Java beans are used for building the re-use applications. Virtual Reality Modeling Language allows to create "virtual worlds" networked via the Internet and hyperlinked with the World Wide Web. JDBC for data base connectivity. Web Database Interface (WDBI) can create databases with much greater ease, using secure ASP forms. When using WDBI to create databases you can Search, Sort, Edit and Delete records in your online database just as easy as typing in a word processor. XML to store web page data in the form of XML files. DHTML to add interactivity to the web pages.

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Web Technologies •

HTML

•

JavaScript

•

JSP

•

Java

•

Java Beans

•

VRML

•

JDBC

•

Web/Database Interfaces

•

XML

•

DHTML

HTML: HTML stands for Hyper Text Markup Language. It is defined using SGML (Standard Generalized Markup Language) and provides tags to identify document structure for later formatting and links to other documents.

USES: •

formatting text on a web page and creating links to other web pages

•

using images and image maps

•

creating forms

•

creating tables

•

creating frames

JavaScript 3 Email: [email protected]

Visit: www.geocities.com/chinna_chetan05/forfriends.html Java script is a web scripting language which can add interactivity and function to a web site. Some examples include drop down menus navigation button effects, interactive forms, slide shows, and pop open windows. There are many applications available to enrich a web site.

USES: We will use java script on the web to perform the client side validation which will reduce the network traffic. Example: Let us consider Yahoo mail server Interface

With out entering anything if we click on Sign In button this request is send to the web server via the web browser with empty values at the sever side is checked that entered values are not matching with the stored values. Immediately web server page will give the response as invalid user name and password. Although there are no values in Id and Pass word field unnecessarily request is send to server page in this way it is increasing the network traffic. Java Script is providing the solution for this problem by validating the web page details at client side. Here we can write one script to check whether user has entered any values are not if yes we are forwarding the request to the web server if not we are not at all forwarding the request to the web server rather we display some message saying that enter some values to the fields.

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JSP: Java Server Page (JSP) is a technology for controlling the content or appearance of Web pages through the use of servlets, small programs that are specified in the Web page and run on the Web server to modify the Web page before it is sent to the user who requested it. Sun Microsystems, the developer of Java, also refers to the JSP technology as the Servlet application program interface (API). JSP is comparable to Microsoft's Active Server Page (ASP ) technology. Whereas a Java Server Page calls a Java program that is executed by the Web server, an Active Server Page contains a script that is interpreted by a script interpreter (such as VBScript or JScript) before the page is sent to the user. An HTML page that contains a link to a Java servlet is sometimes given the file name suffix of .JSP.

JAVA: •

Java is a programming language expressly designed for use in the distributed

environment of the Internet. It was designed to have the "look and feel" of the C++ language, but it is simpler to use than C++ and enforces an object-oriented programming model. Java can be used to create complete applications that may run on a single computer or be distributed among servers and clients in a network. It can also be used to build a small application module or applet for use as part of a Web page. Applets make it possible for a Web page user to interact with the page. •

The major characteristics of Java are:

•

The programs you create are portable in a network. Your source program is

compiled into what Java calls bytecode, which can be run anywhere in a network on a server or client that has a Java virtual machine . The Java virtual machine interprets the bytecode into code that will run on the real computer hardware. This means that individual computer platform differences such as instruction lengths can be recognized and accommodated locally just as the program is being executed. Platform-specific versions of your program are no longer needed.

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The code is robust , here meaning that, unlike programs written in C++ and

perhaps some other languages, the Java objects can contain no references to data external to themselves or other known objects. This ensures that an instruction can not contain the address of data storage in another application or in the operating system itself, either of which would cause the program and perhaps the operating system itself to terminate or "crash." The Java virtual machine makes a number of checks on each object to ensure integrity. •

Java is object-oriented, which means that, among other characteristics, an

object can take advantage of being part of a class of objects and inherit code that is common to the class. Objects are thought of as "nouns" that a user might relate to rather than the traditional procedural "verbs." A method can be thought of as one of the object's capabilities or behaviors. •

In addition to being executed at the client rather than the server, a Java applet

has other characteristics designed to make it run fast. •

Relative to C++, Java is easier to learn.

•

Java was introduced by Sun Microsystems in 1995 and instantly created a new

sense of the interactive possibilities of the Web. Both of the major Web browsers include a Java virtual machine. Almost all major operating system developers (IBM, Microsoft, and others) have added Java compilers as part of their product offerings. •

The Java virtual machine includes an optional just-in-time compiler that

dynamically compiles bytecode into executable code as an alternative to interpreting one bytecode instruction at a time. In many cases, the dynamic JIT compilation is faster than the virtual machine interpretation. •

JavaScript should not be confused with Java. JavaScript, which originated at

Netscape, is interpreted at a higher level, is easier to learn than Java, but lacks some of the portability of Java and the speed of bytecode. Because Java applets will run on almost any operating system without requiring recompilation and because Java has no operating system-unique extensions or variations, Java is generally regarded as the most strategic language in which to develop applications for the Web.

JavaBeans: 6 Email: [email protected]

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JavaBeans is an object-oriented programming interface from Sun Microsystems

that lets you build re-useable applications or program building blocks called components that can be deployed in a network on any major operating system platform. Like Java applet, JavaBeans components can be used to give World Wide Web pages interactive capabilities such as computing interest rates or varying page content based on user or browser characteristics. •

From a user's point-of-view, a component can be a button that you interact with or

a small calculating program that gets initiated when you press the button. From a developer's point-of-view, the button component and the calculator component are created separately and can then be used together or in different combinations with other components in different applications or situations. •

When the components or Beans are in use, the properties of a Bean (for example,

the background color of a window) are visible to other Beans and Beans that haven't "met" before can learn each other's properties dynamically and interact accordingly. •

Beans are developed with a Beans Development Kit (BDK) from Sun and can be

run on any major operating system platform (Windows 95, UNIX, Mac) inside a number of application environments (known as containers), including browsers, word processors, and other applications. •

To build a component with JavaBeans, you write language statements using Sun's

Java programming language and include JavaBeans statements that describe component properties such as user interface characteristics and events that trigger a bean to communicate with other beans in the same container or elsewhere in the network. •

Beans also have persistence, which is a mechanism for storing the state of a

component in a safe place. This would allow, for example, a component (bean) to "remember" data that a particular user had already entered in an earlier user session. JavaBeans gives Java applications the compound document capability that the OpenDoc and ActiveX interfaces already provide.

VRML: 7 Email: [email protected]

Visit: www.geocities.com/chinna_chetan05/forfriends.html VRML Virtual Reality Modeling Language VRML allows to create "virtual worlds" networked via the Internet and hyperlinked with the World Wide Web. Aspects of virtual world display, interaction and internetworking can be specified using VRML without being dependent on special gear like head-mounted devices (HMD). It is the intention of its designers to develop VRML as the standard language for interactive simulation within the World Wide Web.

JDBC: The JDBC API is the industry standard for database-independent connectivity between the Java programming language and a wide range of databases. The JDBC API provides a call-level API for SQL-based database access. JDBC technology allows you to use the Java programming language to exploit "Write Once, Run Anywhere" capabilities for applications that require access to enterprise data.

JDBC API Overview The JDBC API makes it possible to do three things: •

Establish a connection with a database or access any

tabular data source •

Send SQL statements

•

Process the results

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Web-Database Interfaces: Web Database Interface (WDBI) can create databases with much greater ease, using secure ASP forms. When using WDBI to create databases you can Search, Sort, Edit and Delete records in your online database just as easy as typing in a word processor. 1.select the database 2.set the table field options 3.choose the color scheme 4.choose the language 5.test it 6.click on the build button

When using this program and building your ASP Database it will be ready to upload complete with the HTML or JavaScript that you need. AWDIB is a complete database solution. No additional plug-ins are required, there is no difficult configurations to set. We can SQL as Querying language. SQL stands for structured query language.

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XML: XML stands for Extended Markup Language by using which we can store the in the XML files. If we consider the HTML by using which we can describe the data but we can’t store the data. but in web environment we have store data. We can achieve that by using XML. All web pages contents in the back end databases are stored in the form of the XML files.

DHTML: DHTML stands for Dynamic Hypertext Markup Language by using which we can add interactivity to the web pages by using cascading style sheets and java script. DHTML = HTML + CSS + JavaScript

References: ♦ www.w3schools.com/html ♦ www.wikipedia.com/jsp

♦ Java complete reference by Herbetz schilt ♦ HTML Black pad book

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