Notes

Election Management System Overview

• Web-based voting application with user authentication
• Components: Login, Candidate List, Voting, Results
• Flow: Signup → Login → Vote → Logout
• Admin features: Candidate management (CRUD operations)

Inter-Servlet Communication

Navigation Methods

1. Redirection (resp.sendRedirect())
   • Client receives 302 status code
   • Browser makes new request to different URL
   • URL changes in browser
   • Can navigate to any page (internal/external)
   • Slower (two HTTP requests)
   • Useful after POST requests (PRG pattern)
2. Forward (RequestDispatcher.forward())
   • Server-side navigation
   • Same request object passed to next servlet
   • URL unchanged in browser
   • Only within same web application
   • Faster (single request)
   • Final response generated by target page
3. Include (RequestDispatcher.include())
   • Includes response from another servlet
   • Same request object shared
   • URL unchanged in browser
   • Only within same web application
   • Response sent by first page

PRG Pattern (Post-Redirect-Get)

• Prevents duplicate form submissions on refresh
• After POST request, redirect to GET request
• Avoids data being posted twice to database

State Management

Overview

• State Management: Maintaining client information across requests
• Client-side: Less secure, reduces server load, increases network traffic
• Server-side: More secure, increases server memory usage