Learn Java for Web Development

CHAPTER 2: Building Web Applications Using Servlets and JSP 51

Modify the generated HelloWorld class with the code in Listing 2-1.

Listing 2-1. HelloWorld Servlet

1.package apress.helloworld;
2.
3.import java.io.IOException;
4.import java.io.PrintWriter;
5.
6.import javax.servlet.http.HttpServlet;
7.import javax.servlet.http.HttpServletRequest;
8.import javax.servlet.http.HttpServletResponse;
9.
10.public class HelloWorld extends HttpServlet{
11.
12.protected void doGet(HttpServletRequest request,
13.HttpServletResponse response)
14.{
15.try
16.{
17.response.setContentType("text/html");
18.PrintWriter printWriter = response.getWriter();
19.printWriter.println("

");
20.printWriter.println("Hello World");
21.printWriter.println("

");
22.}
23.catch (IOException ioException)
24.{
25.ioException.printStackTrace();
26.}
27.}
28.
29.}

Modify the web.xml file with the code in Listing 2-2.

Listing 2-2. Web.xml: Deployment Descriptor

1.<?xml version="1.0" encoding="UTF-8"?>
2.<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
3.xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
4.xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
5.id="WebApp_ID" version="3.0">
6.helloworld
7.
8.HelloWorld
9.apress.helloworld.HelloWorld
10.
11.
12.HelloWorld