Nancyvarkey at 08:58, 13 April 2015

2015-04-13T08:58:47Z

PoojaMoolya at 09:56, 25 June 2014

2014-06-25T09:56:48Z

Arya Ratish: Created page with ''''Title of script''': Servlet Methods '''Author: arya ''' '''Keywords: servlets, video tutorial, GET, POST''' {| style="border-spacing:0;" | style="border:1pt solid #000000…'

2013-08-23T12:18:26Z

Created page with ''''Title of script''': Servlet Methods '''Author: arya ''' '''Keywords: servlets, video tutorial, GET, POST''' {| style="border-spacing:0;" | style="border:1pt solid #000000…'

New page

'''Title of script''': Servlet Methods

'''Author: arya '''

'''Keywords: servlets, video tutorial, GET, POST'''

{| style="border-spacing:0;"
| style="border:1pt solid #000000;padding:0.097cm;"| <center>'''Visual Cue'''</center>
| style="border:1pt solid #000000;padding:0.097cm;"| <center>'''Narration'''</center>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 1
| style="border:1pt solid #000000;padding:0.097cm;"| Welcome to the spoken-tutorial on''' Servlet Methods.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 2
| style="border:1pt solid #000000;padding:0.097cm;"| In this tutorial we will learn to

* create a simple login form using '''JSP'''
* Pass parameters using '''doGet''' '''method'''
* Pass parameters using '''doPost method'''
* Difference between''' doGet '''and '''doPost''' methods

|-
| style="border:1pt solid #000000;padding:0.106cm;"| Slide 3

Software Requirements
| style="border:1pt solid #000000;padding:0.106cm;"| Here we are using

* Ubuntu Version 12.04
* Netbeans IDE 7.3
* JDK 1.7
* Firefox web-browser 21.0

You can use any web-browser of your choice.

|-
| style="border:1pt solid #000000;padding:0.106cm;"| Slide 4

Prerequisites
| style="border:1pt solid #000000;padding:0.106cm;"| To follow this tutorial you must know

* Core Java using '''Netbeans IDE'''
* '''HTML'''
* Basics of '''Java Servlets '''and '''JSPs'''

If not, for relevant tutorials please visit our website.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 5
| style="border:1pt solid #000000;padding:0.097cm;"| We will begin by creating our web application- the '''Library Management System.'''

First, we will create the '''home page.'''

The '''home page''' will contain a simple '''login form'''.

It will allow authenticated users to login to the '''Library Management System.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Switch to '''Netbeans IDE.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Now, let us switch to '''Netbeans IDE.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Switch to '''index.jsp '''page.
| style="border:1pt solid #000000;padding:0.097cm;"| Let us go to the '''index '''''dot '''''jsp '''page, that we had already modified earlier.

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| I have modified this page to create our '''home page.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the '''title.'''
| style="border:1pt solid #000000;padding:0.097cm;"| We keep the '''title '''as '''Home Page.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''table '''and '''border<nowiki>=1</nowiki>'''
| style="border:1pt solid #000000;padding:0.097cm;"| Inside the body, we have a '''table, '''with '''border '''''equal to '''''1.'''

You can have a look at the code here.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''Welcome to Library Management System.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Inside the '''table, '''we have included a '''heading, Welcome to Library Management System.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''This is the home page for Library Management System.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Next, we have '''paragraph tag '''that includes, '''This is the home page for Library Management System.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the line containing hyperlink.
| style="border:1pt solid #000000;padding:0.097cm;"| Then, we have a '''hyperlink, '''which links to a page called '''visitorHomePage '''''dot '''''jsp.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| We will create this page later.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''form.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Next,we have a very simple''' login form.'''

This form allows a '''registered user''' to '''login''' .

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Before creating the '''form '''we will have to create a '''servlet '''named '''GreetingServlet.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Pause the tutorial and create a new '''servlet '''as explained in the earlier tutorial.

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Note that the '''servlet name '''is '''GreetingServlet.'''

The '''URL pattern '''should be '''GreetingServletPath.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| This''' form''' has two input elements - '''Username and Password.'''

It also has a '''Submit button '''that says '''Sign In.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''paragraph tag.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Next, we have a '''paragraph tag '''that includes a link to '''addUser.jsp.'''

This is the''' registration page''' for those '''users''' who have not yet registered.

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Now, let us go to our GreetingServlet.java.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''org.spokentutorial.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Note that '''GreetingServlet.java '''is created in the same package '''org.spokentutorial.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''request object.'''
| style="border:1pt solid #000000;padding:0.097cm;"| This '''servlet '''will be able to access the '''form data '''from the '''request object.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Point to '''MyServlet.'''
| style="border:1pt solid #000000;padding:0.097cm;"| This '''servlet '''will act as a '''controller.'''

Do you recall that we had come across '''controller '''earlier?

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 6
| style="border:1pt solid #000000;padding:0.097cm;"| Now, we will see what the '''servlet '''does as a '''controller.'''

The '''form data''' will reside in the '''request object.'''

The first task is to retrieve the '''form''' data parameters.

This is done using the '''getParameter method '''on the '''request object.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Switch to '''Netbeans IDE.'''
| style="border:1pt solid #000000;padding:0.097cm;"| So, let us switch to '''Netbeans IDE.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type '''PrintWriter out =response.getWriter();'''
| style="border:1pt solid #000000;padding:0.097cm;"| Type inside the''' doGet method,'''

'''PrintWriter ''space ''out ''equal to ''response ''dot ''getWriter''.'''''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Next, we will retrieve the '''form data '''parameters.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type '''String username<nowiki>=</nowiki>request.getParameter(“userName”);'''

| style="border:1pt solid #000000;padding:0.097cm;"| So on the next line type,

'''String ''space ''username ''equal to ''request ''dot ''getParameter ''within brackets and double quotes ''userName ''semicolon''.'''

Note that this '''userName '''is the name we have included in the '''form tag '''for '''User Name.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type '''String password<nowiki>=</nowiki>request.getParameter(“password”);'''
| style="border:1pt solid #000000;padding:0.097cm;"| Similarly, we will retrieve the '''password''' also.

So on the next line, type, '''String '''''space '''''username '''''equal to '''''request ''dot ''getParameter ''within brackets and double quotes ''password ''semicolon''.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Next, we will print the '''User Name '''in the '''output'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| '''out.println(“Hello from GET Method” + username);'''
| style="border:1pt solid #000000;padding:0.097cm;"| So, on the next line type

'''out ''dot ''println ''within brackets and double quotes ''Hello from GET Method plus username''.'''''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Right click on '''MyFirstProject.'''
| style="border:1pt solid #000000;padding:0.097cm;"| <nowiki><</nowiki>Pause>

To run this project, '''right-click''' on '''MyFirstProject. '''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Click on '''Clean and Build.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Click on '''Clean and Build.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Right click on '''MyFirstProject '''and click on '''Run.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Again right click on '''MyFirstProject '''and click on '''Run.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Hover your mouse over the console.
| style="border:1pt solid #000000;padding:0.097cm;"| The '''server '''is up and running.

It has deployed '''MyFirstProject.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Hover your mouse over the '''Home Page.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Now, we have got our '''home page '''displayed in the '''browser'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Point the mouse to the '''title.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Observe that the '''title '''of the page is '''Home Page.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Hover your mouse over the login form.
| style="border:1pt solid #000000;padding:0.097cm;"| We can see a very simple '''login form''' here.

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Let me enter the '''Username '''and '''Password.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type '''spoken '''in the '''textbox.'''
| style="border:1pt solid #000000;padding:0.097cm;"| I will type '''arya '''as the '''Username.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type '''spoken<nowiki>*123 </nowiki>'''as the '''Password.'''
| style="border:1pt solid #000000;padding:0.097cm;"| And '''arya<nowiki>*123 </nowiki>'''as the '''Password.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Click on '''Sign In.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Then click on '''Sign In.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Hover your mouse over the browser window.
| style="border:1pt solid #000000;padding:0.097cm;"| We can see that we have got the output '''Hello from GET Method''' '''arya'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Now, the '''user '''was able to login here because we have not included any validation inside the code. We will do this in the later tutorial.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the form data.

Highlight the question mark.
| style="border:1pt solid #000000;padding:0.097cm;"| Now, have a look at the '''URL '''here.

It is '''localhost '''''colon '''''8080 '''''slash '''''MyFirstProject '''''slash '''''GreetingServletPath '''''question mark '''''userName '''''equal to '''''arya&password '''''equal to '''''arya<nowiki>*123.</nowiki>'''

The '''form data '''is separated from the page information by a ''question mark.''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight '''userName<nowiki>=</nowiki>spoken&password<nowiki>=</nowiki>spoken<nowiki>*123</nowiki>'''
| style="border:1pt solid #000000;padding:0.097cm;"| We can see the '''username '''and '''password '''that we had entered in the '''form is '''inside the URL also.

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Now, let us try '''to do''' the same using '''POST Method.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Switch back to the '''IDE.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Switch back to the '''IDE.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Copy the code we had written for the '''doGet Method '''and paste it in the '''doPost Method.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Copy the code we had written for the '''doGet Method '''and paste in the '''doPost Method.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Change '''GET '''to '''POST.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Now, change the '''println''' statement to '''Hello from POST Method.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Open '''index.jsp.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Now, let us open '''index '''''dot '''''jsp.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Change '''GET '''to '''POST'''
| style="border:1pt solid #000000;padding:0.097cm;"| Here, we must change the '''method attribute '''of the '''form tag '''to '''POST.'''

You can have a look at this code now.

We have '''form action '''''equal to '''''GreetingServletPath method '''''equal to '''''POST.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type '''method<nowiki>=”</nowiki>POST”.'''
| style="border:1pt solid #000000;padding:0.097cm;"| Now, we will r'''un this Project again'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Right click on '''MyFirstProject '''and click '''on Run'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the output.
| style="border:1pt solid #000000;padding:0.097cm;"| We have got an output similar to the one we got, when we used the '''GET method.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| So let us type the '''User Name '''and '''Password '''again.

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Then click on '''Sign In.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Note that we have got '''Hello from POST Methodarya.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Now, take a look at the '''URL.'''

'''localhost '''''colon '''''8080 '''''slash '''''MyFirstProject '''''slash '''''GreetingServletPath '''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Here we do not see the '''form data '''in the '''URL '''of the '''request.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| This is the major difference between '''doGet '''and '''doPost Methods.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| '''Slide 7'''

'''When to use GET and POST Methods?'''
| style="border:1pt solid #000000;padding:0.097cm;"| Now, let us learn when to use '''GET '''and when to use '''POST Methods.'''

'''GET Method '''is used when:

* the '''form '''is small and hence the '''data '''is less.
* the '''user''' wants the contents of the data to be visible in the '''URL.'''

'''POST Method '''is used when:

* the '''form '''is large and hence the '''data '''is more.
* the '''user''' does not want the contents of the data to be visible in the '''URL.'''

ex: '''passwords'''

<nowiki><</nowiki>Pause>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 9

Summary
| style="border:1pt solid #000000;padding:0.097cm;"| Let us summarize.

In this tutorial we have learnt to:

* create a simple login form using '''JSP'''
* Pass parameters using '''doGet''' '''method'''
* Pass parameters using '''doPost method'''
* Difference between''' doGet '''and '''doPost''' methods

|-
| style="border:1pt solid #000000;padding:0.097cm;"|
| style="border:1pt solid #000000;padding:0.097cm;"| Please make sure that you have completed this tutorial before proceeding further.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 10

About slide

| style="border:1pt solid #000000;padding:0.097cm;"| Watch the video available at the following link.

* It summarizes the Spoken Tutorial Project
* If you do not have good bandwidth you can download and watch it

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 11

About slide
| style="border:1pt solid #000000;padding:0.097cm;"| The Spoken Tutorial Project Team

* Conducts workshops using spoken tutorials
* Gives certificates for those who pass an online test
* For more details please write to contact at spoken hyphen tutorial dot org

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 12

Acknowledgement
| style="border:1pt solid #000000;padding:0.097cm;"| Spoken Tutorial Project is a part of the Talk to a Teacher Project

* It is supported by the National Mission on Education through ICT, MHRD, Government of India
* More information on this mission is available at
* http://spoken-tutorial.org/NMEICT-Intro

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 13

Contributor Slide
| style="border:1pt solid #000000;padding:0.097cm;"| The Library Management System has been contributed by a leading software MNC, through their Corporate Social Responsibility Programme.

They have also validated the content for this spoken tutorial.

This is Arya Ratish from IIT Bombay signing off.

Thank you for joining.

|}

@@ Line 247: / Line 247: @@
 |-
-| style="border:1pt solid #000000;padding:0.097cm;"| Type '''spoken<nowiki>*123 </nowiki>'''as the '''Password.'''
+| style="border:1pt solid #000000;padding:0.097cm;"| Type '''arya<nowiki>*123 </nowiki>'''as the '''Password.'''
 | style="border:1pt solid #000000;padding:0.097cm;"| And '''arya<nowiki>*123 </nowiki>'''as the '''Password.'''

@@ Line 4: / Line 4: @@
 '''Keywords: servlets, video tutorial, GET, POST'''
 {| style="border-spacing:0;"
 | style="border:1pt solid #000000;padding:0.097cm;"| <center>'''Visual Cue'''</center>

Java-Business-Application/C2/Servlet-Methods/English - Revision history

Nancyvarkey at 08:58, 13 April 2015

PoojaMoolya at 09:56, 25 June 2014

Arya Ratish: Created page with ''''Title of script''': Servlet Methods '''Author: arya ''' '''Keywords: servlets, video tutorial, GET, POST''' {| style="border-spacing:0;" | style="border:1pt solid #000000…'