December 2003
Intermediate to advanced
764 pages
24h 58m
English
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Reading a Request
One of the
arguments
passed to the doGet( ) and doPost(
) methods is an object that implements the
HttpServletRequest
interface. This interface defines methods that provide access to a
wealth of information about the request. Example 19-2
illustrates the use of the most common methods.
Example 19-2. Using HttpServletRequest methods
import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class HelloYou extends HttpServlet {
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
String name = request.getParameter("name");
if (name == null) {
name = "you";
}
response.setContentType("text/html");
PrintWriter out = response.getWriter( );
out.println("<html><body>");
out.println("<h1>Hello " + name + "</h1>");
out.println("I see that:<ul>");
String userAgent = request.getHeader("User-Agent");
out.println("<li>your browser is: " + userAgent);
String requestURI = request.getRequestURI( );
out.println("<li>the URI for this page is: " +
requestURI);
String contextPath = request.getContextPath( );
out.println("<li>the context path for this app is" +
contextPath);
String servletPath = request.getServletPath( );
out.println("<li>this servlet is mapped to: " +
servletPath);
String pathInfo = request.getPathInfo( );
out.println("<li>the remaining path is: " + pathInfo);
Map parameters = request.getParameterMap( ); out.println("<li>you sent the following params:<ul>"); Iterator ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.