Learn Java for Web Development

70 CHAPTER 2: Building Web Applications Using Servlets and JSP

15.private static final long serialVersionUID = 1L;
16.

17. /**


18. 
    
    
    
    • @see HttpServlet#HttpServlet()
    
    
    
    


19. */


20. public HelloWorld() {


21. super();


22. // TODO Auto-generated constructor stub


23. }


24. 
    

    25./**

    
    


25. 
    
    
    
    • @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    
    
    
    


26. */
    28.protected void doGet(HttpServletRequest request, HttpServletResponse response) throws
    ServletException, IOException {
    29.// TODO Auto-generated method stub
    30.}


27. 
    

    32./**

    
    


28. 
    
    
    
    • @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    
    
    
    


29. */
    35.protected void doPost(HttpServletRequest request, HttpServletResponse response) throws
    ServletException, IOException {
    36.// TODO Auto-generated method stub
    37.}


30. 
    

    39.}

    
    

   Line 13: This line shows the usage of the @WebServlet annotation. The

HelloWorld servlet is decorated with the @WebServlet annotation to specify

the name, URL pattern, initialization parameters, and other configuration items

usually specified in the web.xml deployment descriptor.

   Line 14: This line shows that the HelloWorld servlet extends the HTTPServlet.

   Lines 28 to 37: These lines show the doGet and doPost methods generated by

the IDE.

Add the code in Listing 2-13 to the doGet method of the HelloWorld servlet.

Listing 2-13. Printing “Hello World”

PrintWriter out = response.getWriter();
out.println("

Hello World !

You will have to import java.io.Printwriter. You can do this in Eclipse by selecting Source ➤
Add Import or by pressing Ctrl+Shift+M; now you can run the application on the server. Right-click
HelloWorld.java in the helloworld project in Eclipse and then select Run As ➤ Run on Server. The
server you are using in this case is Tomcat 7.0. Then use the following URL to access the application:

http://localhost:8080/helloworld/HelloWorld