• In order to make data and resource of the application as globally accessible data and resources,  we need to develop our application as web application
  • Web Application:-
    • it is a collection of web resource
      • Eg: html file , image files, Servlet programs, jsp programs and etc
    • It is a collection of static and dynamic web resource programs.
    • Static web resource generates static web page and dynamic web resource programs generates dynamic web pages.
      • Eg:  static web pages are like html program and dynamic web pages  are like Servlet, jsp programs
  • Website:- Once web application is placed in the internet network by purchasing domain name like yahoo.com and by purchasing space then the web application is called as website
  • Web application development models:
    • Model 1: developing web application by using only Servlet / Jsp
    • Model 2: it is also called as Model View Controller (MVC). Developing web application by using multiple technologies like Servlet, jsp, ejb, hibernates, spring and etc.
  • Background:
    • In the initial days of web application development programmer have preferred to develop model 1 architecture based web application
    • But now-a-days programmers are preferring to develop MVC architecture based web application
  • Standard Logic: Every web application contains the following logic either in one web resource program or in mulitple web resource programs
    • Basic Logics:
      • Request Data gathering logic: this logic gathers input values of web resource from end-user through browser window as form page form data.
      • Form validation logic: this logic checks the format and pattern of the form data to validate form data eg. Checked weather required fields are typed or not
      • Business logic: the main logic of the application which generates results based on input values, this logic is also called as Request processing logic
      • Persistence logic: the logic that interacts with db s/w and manipulate table data eg; jdbc code
      • Presentation logic: the logic the generate user interface for end user  and that can send formatted result to browser as response
      • Middleware service: the additional service which can be configured on the application from outside the application to make them as perfect and accurate application. eg: security Tax, jdbc connection pooling and etc
      • Session management: the logic that remember client data across the multiple request by using session tracking techniques eg: hidden from fields, cookies, http session with cookies