Introduction to Web Application

Introduction to Web Application

Suresh

--

Dear Friends https://www.Pinepad.in welcomes you to start Spring Boot for Beginners course. This is course designed for those who don’t have knowledge of Web Application concepts. I will be going to teach you the fundamentals. In order to continue this course, you must know the fundamentals of Java Programming. Please learn Java programming and come back and read this tutorial to become a Spring Boot Programmer.

What is a Web Application?
If you say any software is a Web Application, it must have two layers which are Client and Server. The following diagram explains the Web Application Architecture flow.

The client is purely developed using HTML/CSS and JavaScript and the Server is purely developed by some Server-side programming language. In our case, our side programming is Java. The client always requests the data to Server and the Server takes the request from the Client, if the request is valid, the Server sends the data to the Client(This is called a response). So, a request is coming from the client and a response is coming from the Sever. Request and response nothing but simple data only. These data should understand both Client/Server to perform smooth communication.
For example:
Let say, a user entering the Credential in the login form which is the username and password. This is called request data. The server receives the request data, if the requested data is available in the Sever(username password exists), The server allows to login and send all user information to the client. This is called Response data.

How people develop Web Application 15 years back using Java?
15 years back If you want to develop any web application using Java you have to know the following technologies.
Java,
JSP,
Servlet
Tomcat Server
HTML/JavaScript
Without using the above technologies, we can’t implement Web Application. Now we will be going to see the concepts of Servlet, JSP, and Tomcat Server. then we will be implementing Web Application these Technologies.

What is Web Server?
The Web Server is software, we can install that on our computer and it runs under a specific unique port in the computer. In our case, Tomcat is a Web Server which we can install on our computer and it runs under 8080 port number. In our computer, we can install multiple Web Server and each Web Server should run under one unique port number. let say we have installed two Tomcat Server. both Servers are run under a unique port number. Below pictorial diagram explains how multiple Web Server run in a single Computer

Two Web Server is running in a Computer with different unique Port

According to the above diagram, two Web Servers are running in a single machine with different ports. Port is a kind of address to access a particular Web Server from the Computer. “localhost” nothing but a computer where I installed Web Servers and 8080 and 8081 are ports to access a particular Web Server. I am accessing these servers using the HTTP protocol

For further reading please click the below link.
Introduction to Web Application

--

--