Java-Business-Application/C2/Java-servlets-and-JSPs/English-timed

Time	Narration
00:01	Welcome to the spoken-tutorial on Java Servlets and JSPs.
00:06	In this tutorial, we will learn about:
00:09	Web server Web container.
00:12	We will also learn to create a simple Java Servlet and JSP.
00:18	Here we are using:
00:20	Ubuntu Version 12.04
00:23	Netbeans IDE 7.3
00:27	JDK 1.7
00:29	Firefox web-browser 21.0.
00:33	You can use any web-browser of your choice.
00:37	To follow this tutorial, you must have knowledge of:
00:41	Core Java using Netbeans IDE and
00:45	HTML.
00:47	If not, for relevant tutorials please visit our website.
00:52	Before moving onto Servlets and JSP, let us first understand a web server.
00:58	A web server is a system that delivers content to end-users over the Internet.
01:05	It is also known as Internet server.
01:10	A web container is a component of the web server that interacts with Java servlets.
01:18	It is also known as servlet container.
01:22	The servlet container allows the servlets to execute inside it.
01:28	Now, let us learn how to write a simple servlet.
01:32	Switch to the Netbeans IDE.
01:35	Click on the Project tab on the left hand side of the IDE.
01:40	Earlier, we had created a simple Project named MyFirstProject.
01:46	You can see it here, on the left hand side of the IDE.
01:50	Let us now create a simple servlet inside this Project.
01:55	So, right-click on MyFirstProject.
01:59	Go to New and click on Servlet.
02:03	A New Servlet window opens.
02:05	Type the Class Name as MyServlet.
02:09	Type the Package name as org.spokentutorial.
02:16	Then click on Next.
02:18	Click on Add information to deployment descriptor (web.xml).
02:23	We can see that the Class Name is org.spokentutorial.MyServlet.
02:30	We can see that the Servlet Name is same as that of the Class Name which is MyServlet.
02:37	Note that the URL pattern is the same name as that of the Class Name. i.e MyServlet.
02:45	We can change it to MyServletPath.
02:50	Then click on Finish.
02:53	The source code created by the IDE for MyServlet.java is seen in the Source Editor window.
03:01	We see MyServlet.java is created in the package org.spokentutorial.
03:09	Notice that the servlet is just like any other Java class
03:14	except that the servlet does not have a main method.
03:19	Now, let us learn something about Glassfish Server.
03:24	A servlet is deployed in a servlet container.
03:28	We are using Glassfish as our server.
03:32	Servlet container is a component of Glassfish that interacts with servlets.
03:39	Now, let us come back to Netbeans IDE.
03:42	Note that MyServlet extends the HttpServlet.
03:48	At the bottom of the code, we can see HttpServlet methods.
03:54	Click on the plus sign on the left to view these methods.
03:59	We see the methods - doGet, doPost and getServletInfo methods.
04:09	We can override these methods.
04:12	We can see that there is one more method named processRequest at the top.
04:18	We will delete processRequest and getServletInfo methods to avoid confusion.
04:25	So, we are left with two methods doGet and doPost.
04:31	For now, we will look at the doGet method.
04:35	doGet is the default method for any simple URLrequest.
04:41	So, we will type some code inside the doGet method.
04:45	We had already deleted processRequest method.
04:49	So, remove the method call for processRequest method.
04:54	Also remove it from the doPost method.
04:58	Now, let us come to the doGet method
05:01	We can see that there are two parameters that are passed to the doGet method.
05:07	One is the request and the other is the response object.
05:12	Also notice that request is of type HttpServletRequest.
05:18	And response object is of type HttpServletResponse.
05:22	We will use the response object to send the HTML response back to the client side.
05:30	For that, we will have to create a PrintWriter object.
05:35	Notice that the PrintWriter class is already imported.
05:40	So, inside the doGet method type: PrintWriter space writer equal to response dot getWriter open and close brackets semicolon.
05:57	Press Enter.
05:59	On the next line, type:
06:02	writer dot println within brackets and double quotes Welcome.
06:09	Then, press Ctrl S to save the file.
06:14	Now, let us run the servlet.
06:17	So, on the left hand side, in the Projects tab right click on MyServlet dot java.
06:24	Then, click on Run File.
06:27	We get a Set Servlet Execution URI dialog box.
06:32	Click on OK.
06:35	When the browser window opens, look at the URL.
06:39	It is localhost colon 8080 slash MyFirstProject slash MyServletPath.
06:47	Here, MyFirstProject is the context name and MyServletPath is the URL pattern that we had set.
06:55	We can see the text Welcome printed on the browser.
07:00	Now go back to the Netbeans IDE.
07:03	In the println method, we can pass html code.
07:07	For example, put Welcome in h3 tag.
07:12	Now, save the file.
07:14	Since we deployed this servlet earlier, we need not run it again.
07:20	The web container automatically detects it.
07:23	So, we can go back to the browser.
07:27	Refresh.We see the message Welcome in a different format.
07:32	Now, come back to the IDE.
07:35	Thus, we have successfully created a servlet.
07:39	We can create any web application using servlets.
07:45	We used the servlet to display an HTML code.
07:49	Notice that we have HTML code inside the Java code.
07:54	Even though this is possible, it is difficult to do for large web applications.
08:00	And hence not a recommended practice.
08:03	It would be better to replace this using JSP or Java Server Pages.
08:10	We will see the use of servlets and JSPs.
08:13	Servlets and JSPs are used together to separate presentation from content.
08:20	Servlets act as the controller and JSPs act as the view .
08:25	Servlets contain HTML code inside Java code.
08:30	JSPs contain Java code inside HTML code.
08:35	We will learn more about these in the coming tutorials.
08:39	Now, switch back to Netbeans IDE.
08:42	We will now create a simple JSP page.
08:47	So, right click on MyFirstProject.
08:50	Go to New and click on JSP.
08:54	A New JSP window opens.
08:57	Type the Filename as welcome.
09:01	And then click on Finish.
09:04	Click on the Projects tab on the left hand side.
09:07	We can see that Welcome.jsp is under Web Pages folder.
09:13	Now, in the editor, change Hello World to Welcome.
09:19	Notice that Welcome is within "h1" tags.
09:23	Now, save the file.
09:25	Come back to the browser.
09:27	In the url, after MyFirstProject slash, type: welcome.jsp.
09:35	We see the output Welcome.
09:38	Therefore, for presentation purpose JSP is preferred.
09:42	Let us summarize.
09:44	In this tutorial, we have learnt:
09:47	About web server and web container.
09:49	To create a simple servlet.
09:52	To create a simple JSP.
09:55	Please make sure that you have completed this tutorial before proceeding further.
10:01	Watch the video available at the following link.
10:04	It summarizes the Spoken Tutorial project.
10:08	If you do not have good bandwidth, you can download and watch it.
10:13	The Spoken Tutorial Project Team:
10:15	Conducts workshops using spoken tutorials.
10:19	Gives certificates to those who pass an online test.
10:22	For more details, please write to: contact at spoken hyphen tutorial dot org.
10:28	Spoken Tutorial Project is a part of the "Talk to a Teacher" project.
10:32	It is supported by the National Mission on Education through ICT, MHRD, Government of India.
10:40	More information on this mission is available at http://spoken-tutorial.org/NMEICT- Intro .
10:50	The Library Management System has been contributed by a leading software MNC through their "Corporate Social Responsibility" program.
11:00	They have also validated the content for this spoken tutorial.
11:04	This is Arya Ratish from IIT Bombay, signing off. Thank you for joining.

Contributors and Content Editors

PoojaMoolya, Pratik kamble, Sandhya.np14