Login page ...

package classExamples;

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class LoginFilter implements Filter{

	public void doFilter(ServletRequest request,
			ServletResponse response,
			FilterChain chain)
		throws IOException, ServletException
	{
	    	
		Object loginStatus = ((HttpServletRequest)request).getSession().getAttribute("isLoggedIn");
		if(loginStatus!=null){
			chain.doFilter(request, response);
		}
		else{
			response.setContentType("text/html");
			PrintWriter toClient = response.getWriter();
			toClient.println("<HTML>");
			toClient.println("<TITLE>Login Page</TITLE>");
			toClient.println("<h1>Login page ... </h1>");
			toClient.println("</HTML>");
			toClient.close();
		}

	}
	public void init(FilterConfig config){}
	public void destroy() {}
}