Difference between revisions of "Java-Business-Application/C2/Java-servlets-and-JSPs/English-timed"

From Script | Spoken-Tutorial
Jump to: navigation, search
Line 29: Line 29:
 
|-
 
|-
 
|  00.20
 
|  00.20
−
| Ubuntu Version 12.04
+
| ''' Ubuntu Version 12.04'''
  
 
|-
 
|-
 
|  00.23
 
|  00.23
−
| Netbeans IDE 7.3
+
| ''' Netbeans IDE 7.3'''
  
 
|-
 
|-
 
|  00.27
 
|  00.27
−
|  JDK 1.7
+
|  '''JDK 1.7'''
  
 
|-
 
|-
Line 73: Line 73:
 
|-
 
|-
 
|  01.05
 
|  01.05
−
| '''It '''is also known as '''Internet server'''.
+
|It is also known as '''Internet server'''.
  
 
|-
 
|-
Line 172: Line 172:
 
|-
 
|-
 
|  03.09
 
|  03.09
−
| '''Notice '''that a '''servlet '''is just like any other '''Java class.'''
+
| Notice that a '''servlet '''is just like any other '''Java class.'''
  
 
|-
 
|-
Line 188: Line 188:
 
|-
 
|-
 
| 03.28
 
| 03.28
−
|'''We are using Glassfish as our server.'''
+
|We are using '''Glassfish''' as our '''server.'''
  
 
|-
 
|-
 
| 03.32
 
| 03.32
−
|Servlet container '''is a''' '''component of''' Glassfish''' that interacts with servlets.
+
|Servlet container is a component of''' Glassfish''' that interacts with servlets.
  
 
|-
 
|-
Line 200: Line 200:
 
|-
 
|-
 
| 03.42
 
| 03.42
−
|  Note that MyServlet '''extends the '''HttpServlet. '''
+
|  Note that MyServlet extends the '''HttpServlet. '''
  
 
|-
 
|-
Line 208: Line 208:
 
|-
 
|-
 
|  03.54
 
|  03.54
−
|  Click on the''' plus sign''''' ''on the left, to view these '''methods'''.
+
|  Click on the''' plus sign''''' on the left, to view these '''methods'''.
  
 
|-
 
|-
 
| 03.59
 
| 03.59
−
|  We '''see''' the methods -'''  doGet''', '''doPost''' and '''getServletInfo''' methods.
+
|  We see the methods -'''  doGet''', '''doPost''' and '''getServletInfo''' methods.
  
 
|-
 
|-
Line 224: Line 224:
 
|-
 
|-
 
|  04.18
 
|  04.18
−
|  We will delete '''processRequest '''and''' getServletInfo''' methods to avoid confusion.
+
|  We will delete '''processRequest '''and '''getServletInfo''' methods to avoid confusion.
  
 
|-
 
|-
 
|  04.25
 
|  04.25
−
|  So we are left with two methods '''doGet '''and '''doPost.'''
+
|  So we are left with two methods '''doGet''' and '''doPost.'''
  
 
|-
 
|-
Line 236: Line 236:
 
|-
 
|-
 
|04.35
 
|04.35
−
|  '''doGet '''is the default '''method''' for any simple '''URL '''request.
+
|  '''doGet'''is the default '''method''' for any simple '''URL'''request.
  
 
|-
 
|-
Line 284: Line 284:
 
|-
 
|-
 
|  05.35
 
|  05.35
−
|  Notice that the '''PrintWriter class '''is already imported'''.'''
+
|  Notice that the '''PrintWriter class '''is already imported.
  
 
|-
 
|-
 
|  05.40
 
|  05.40
−
|  So, inside the '''doGet method '''type '''PrintWriter ''space ''writer ''equal to ''response ''dot ''getWriter ''open and close brackets semicolon'''''
+
|  So, inside the '''doGet method'''type '''PrintWriter ''space ''writer ''equal to ''response ''dot ''getWriter ''open and close brackets semicolon'''''
  
 
|-
 
|-

Revision as of 12:27, 18 September 2014

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
00.10 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 Projects 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 Servlets.
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 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 a servlet is just like any other Java class.
03.14 Except that a 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 doGetis 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 methodtype 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 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.


07.28 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 (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.
08.51 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 for 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

Retrieved from "https://script.spoken-tutorial.org/index.php?title=Java-Business-Application/C2/Java-servlets-and-JSPs/English-timed&oldid=16856"