Difference between revisions of "Java-Business-Application/C2/Servlet-Methods/English-timed"

|-

|-

| Welcome to the spoken-tutorial on  '''Servlet Methods.'''

| Welcome to the spoken-tutorial on  '''Servlet Methods.'''

|-

|-

| In this tutorial we will learn to

| In this tutorial we will learn to

|-

|-

| create a '''simple login form''' using '''JSP'''

| create a '''simple login form''' using '''JSP'''

|-

|-

| Pass parameters using '''doGet''' '''method'''

| Pass parameters using '''doGet''' '''method'''

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|-

| Pass parameters using '''doPost method'''

| Pass parameters using '''doPost method'''

|-

|-

| Difference between '''doGet '''and '''doPost''' methods

| Difference between '''doGet '''and '''doPost''' methods

|-

|-

|Here we are using

|Here we are using

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|-

| '''Ubuntu Version''' 12.04

| '''Ubuntu Version''' 12.04

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|-

| '''Netbeans IDE''' 7.3

| '''Netbeans IDE''' 7.3

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|-

| '''JDK''' 1.7

| '''JDK''' 1.7

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|-

| '''Firefox''' web-browser 21.0

| '''Firefox''' web-browser 21.0

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|-

|You can use any web-browser of your choice.

|You can use any web-browser of your choice.

|-

|-

| To follow this tutorial you must know  

| To follow this tutorial you must know  

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|-

| Core Java using '''Netbeans IDE'''  

| Core Java using '''Netbeans IDE'''  

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|-

| '''HTML'''

| '''HTML'''

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|-

| Basics of '''Java Servlets '''and '''JSPs'''

| Basics of '''Java Servlets '''and '''JSPs'''

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|-

|If not, for relevant tutorials please visit our website.

|If not, for relevant tutorials please visit our website.

|-

|-

| We will begin by creating our web application- the '''Library Management System.'''

| We will begin by creating our web application- the '''Library Management System.'''

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|-

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

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

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|-

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

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

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|-

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

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

|-

|-

| Now, let us switch to '''Netbeans IDE.'''

| Now, let us switch to '''Netbeans IDE.'''

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|-

| Let us go to the '''index ''' '''dot''' '''jsp''' page, that we had already modified earlier.

| Let us go to the '''index ''' '''dot''' '''jsp''' page, that we had already modified earlier.

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|-

| I have modified this page to create our '''home page.'''

| I have modified this page to create our '''home page.'''

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|-

| We keep the '''title '''as '''Home Page.'''

| We keep the '''title '''as '''Home Page.'''

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|-

| Inside the body, we have a '''table,'''with '''border '''''equal to '''''1.'''

| Inside the body, we have a '''table,'''with '''border '''''equal to '''''1.'''

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|-

|You can have a look at the code here.

|You can have a look at the code here.

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|-

| Inside the '''table''' we have included a heading, '''Welcome to Library Management System.'''

| Inside the '''table''' we have included a heading, '''Welcome to Library Management System.'''

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|-

| Next, we have '''paragraph tag''' that includes, '''This is the home page for Library Management System.'''

| Next, we have '''paragraph tag''' that includes, '''This is the home page for Library Management System.'''

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|-

| Then, we have a '''hyperlink,''' which links to a page called '''visitorHomePage ''' '''dot ''' '''jsp.'''

| Then, we have a '''hyperlink,''' which links to a page called '''visitorHomePage ''' '''dot ''' '''jsp.'''

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|-

| We will create this page later.

| We will create this page later.

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|-

| Next,we have a very simple '''login form.'''

| Next,we have a very simple '''login form.'''

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|-

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

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

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|-

| Before creating the '''form ''' you will have to create a '''servlet '''named '''GreetingServlet.'''

| Before creating the '''form ''' you will have to create a '''servlet '''named '''GreetingServlet.'''

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|-

| Pause the tutorial and create a new '''servlet''' as explained in the earlier tutorial.  

| Pause the tutorial and create a new '''servlet''' as explained in the earlier tutorial.  

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|-

| Note that the '''servlet name''' is '''GreetingServlet.'''

| Note that the '''servlet name''' is '''GreetingServlet.'''

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|-

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

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

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|-

| This''' form''' has two input elements - '''Username and Password.'''

| This''' form''' has two input elements - '''Username and Password.'''

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|-

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

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

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|-

| Next, we have a '''paragraph tag''' that includes a link to '''addUser.jsp.'''

| Next, we have a '''paragraph tag''' that includes a link to '''addUser.jsp.'''

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|-

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

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

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|-

| Now, let us go to our '''GreetingServlet.java. '''

| Now, let us go to our '''GreetingServlet.java. '''

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|-

| Note that '''GreetingServlet.java''' is created in the same package '''org.spokentutorial.'''

| Note that '''GreetingServlet.java''' is created in the same package '''org.spokentutorial.'''

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|-

| Now, this '''servlet '''will be able to access the '''form data '''from the '''request object.'''

| Now, this '''servlet '''will be able to access the '''form data '''from the '''request object.'''

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|-

| This '''servlet '''will act as a '''controller.'''

| This '''servlet '''will act as a '''controller.'''

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|-

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

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

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|-

| Now, we will see what the '''servlet '''does as a '''controller.'''

| Now, we will see what the '''servlet '''does as a '''controller.'''

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|-

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

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

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|-

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

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

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|-

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

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

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|-

| So, let us switch to '''Netbeans IDE.'''

| So, let us switch to '''Netbeans IDE.'''

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|-

| Type inside the''' doGet method,'''  

| Type inside the''' doGet method,'''  

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|-

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

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

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|-

| Next, we will retrieve the '''form data '''parameters.

| Next, we will retrieve the '''form data '''parameters.

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|-

| So that on the next line type,  

| So that on the next line type,  

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

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

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|-

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

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

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|-

| Similarly, we will retrieve the '''password''' also.

| Similarly, we will retrieve the '''password''' also.

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|-

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

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

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|-

| Next, we will print the '''User Name '''in the '''output'''.

| Next, we will print the '''User Name '''in the '''output'''.

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|-

| So, on the next line type  

| So, on the next line type  

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

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

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|-

| Now, to run this project, right-click on '''MyFirstProject. '''

| Now, to run this project, right-click on '''MyFirstProject. '''

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|-

| Click on '''Clean and Build.'''

| Click on '''Clean and Build.'''

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|-

| Again right click on '''MyFirstProject ''',  click on '''Run.'''

| Again right click on '''MyFirstProject ''',  click on '''Run.'''

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|-

| So, the '''server '''is up and running.

| So, the '''server '''is up and running.

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|-

|It has deployed '''MyFirstProject.'''

|It has deployed '''MyFirstProject.'''

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|-

|We have got our '''home page '''displayed in the '''browser'''.

|We have got our '''home page '''displayed in the '''browser'''.

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|-

| Observe that the '''title '''of the page is '''Home Page.'''

| Observe that the '''title '''of the page is '''Home Page.'''

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|-

| We can see a very simple '''login form''' here.

| We can see a very simple '''login form''' here.

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|-

| Let me enter the '''Username '''and '''Password.'''

| Let me enter the '''Username '''and '''Password.'''

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|-

| I will type '''arya '''as the '''Username.'''

| I will type '''arya '''as the '''Username.'''

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|-

| And '''arya*123 '''as the '''Password.'''

| And '''arya*123 '''as the '''Password.'''

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|-

| We can see that we have got the output '''Hello from GET Method''' '''arya'''.

| We can see that we have got the output '''Hello from GET Method''' '''arya'''.

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|-

| Now, the '''user '''was able to login here because we have not included any validation inside the code.  

| Now, the '''user '''was able to login here because we have not included any validation inside the code.  

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|-

| We will do this in the later tutorial.  

| We will do this in the later tutorial.  

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|-

| Now, have a look at the '''URL '''here.

| Now, have a look at the '''URL '''here.

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|It is '''localhost '''''colon '''''8080 '''''slash '''''MyFirstProject '''''slash '''''GreetingServletPath '''''question mark '''''userName '''''equal to '''''arya and password '''''equal to '''''arya *123.

|It is '''localhost '''''colon '''''8080 '''''slash '''''MyFirstProject '''''slash '''''GreetingServletPath '''''question mark '''''userName '''''equal to '''''arya and password '''''equal to '''''arya *123.

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|-

|Now, '''form data '''is separated from the page information by a '''question mark.'''

|Now, '''form data '''is separated from the page information by a '''question mark.'''

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|-

| We can see that '''username '''and '''password '''that we had entered in the form is inside the URL also.

| We can see that '''username '''and '''password '''that we had entered in the form is inside the URL also.

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|-

| Now, let us try to do the same using '''POST Method.'''

| Now, let us try to do the same using '''POST Method.'''

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|-

| So, switch back to the '''IDE.'''

| So, switch back to the '''IDE.'''

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|-

| Copy the code we had written for  '''doGet Method '''and paste in the '''doPost Method.'''

| Copy the code we had written for  '''doGet Method '''and paste in the '''doPost Method.'''

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|-

| Now, change the '''println''' statement to '''Hello from POST Method.'''

| Now, change the '''println''' statement to '''Hello from POST Method.'''

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|-

| Now, let us open '''index''' dot '''jsp.'''

| Now, let us open '''index''' dot '''jsp.'''

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|-

| Here, we must change the '''method attribute '''of the '''form tag '''to '''POST.'''

| Here, we must change the '''method attribute '''of the '''form tag '''to '''POST.'''

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|-

|You can have a look at this code now.

|You can have a look at this code now.

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|-

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

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

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|-

| Now, we will run this Project again

| Now, we will run this Project again

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|-

| So, Right click on '''MyFirstProject '''and click on '''Run'''

| So, Right click on '''MyFirstProject '''and click on '''Run'''

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|-

| We have got an output similar to the one we got, when we used the '''GET method.'''

| We have got an output similar to the one we got, when we used the '''GET method.'''

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|-

| So let us type  '''User Name '''and '''Password '''again.

| So let us type  '''User Name '''and '''Password '''again.

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|-

| Then click on '''Sign In.'''

| Then click on '''Sign In.'''

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|-

| Note that we have got '''Hello from POST Method arya.'''

| Note that we have got '''Hello from POST Method arya.'''

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|-

| Now, take a look at the '''URL.'''

| Now, take a look at the '''URL.'''

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|It is '''localhost '''''colon '''''8080 '''''slash '''''MyFirstProject '''''slash '''''GreetingServletPath '''

|It is '''localhost '''''colon '''''8080 '''''slash '''''MyFirstProject '''''slash '''''GreetingServletPath '''

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|-

| Here we do not see the '''form data '''in the '''URL '''of the '''request.'''

| Here we do not see the '''form data '''in the '''URL '''of the '''request.'''

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|-

| This is the major difference between '''doGet '''and '''doPost Methods.'''

| This is the major difference between '''doGet '''and '''doPost Methods.'''

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|-

| Now, let us learn when to use '''GET '''and when to use '''POST Methods.'''

| Now, let us learn when to use '''GET '''and when to use '''POST Methods.'''

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|-

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

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

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|-

| the '''form '''is small and hence the '''data '''is less.

| the '''form '''is small and hence the '''data '''is less.

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|-

| the '''user''' wants the contents of the data to be visible in the '''URL.'''

| the '''user''' wants the contents of the data to be visible in the '''URL.'''

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|-

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

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

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|-

| the '''form '''is large and hence the '''data '''is more.

| the '''form '''is large and hence the '''data '''is more.

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|-

| the '''user''' does not want the contents of the data to be visible in the '''URL.'''

| the '''user''' does not want the contents of the data to be visible in the '''URL.'''

|-

|-

|ex: '''passwords'''

|ex: '''passwords'''

|-

|-

| Let us summarize.

| Let us summarize.

|-

|-

|In this tutorial we have learnt to:

|In this tutorial we have learnt to:

|-

|-

| create a simple login form using '''JSP'''

| create a simple login form using '''JSP'''

|-

|-

| Pass parameters using '''doGet''' '''method'''

| Pass parameters using '''doGet''' '''method'''

|-

|-

| Pass parameters using '''doPost method'''

| Pass parameters using '''doPost method'''

|-

|-

| Difference between''' doGet '''and '''doPost''' methods

| Difference between''' doGet '''and '''doPost''' methods

|-

|-

| Please make sure that you have completed this tutorial before proceeding further.

| Please make sure that you have completed this tutorial before proceeding further.

|-

|-

| Watch the video available at the following link.

| Watch the video available at the following link.

|-

|-

| It summarizes the Spoken Tutorial Project

| It summarizes the Spoken Tutorial Project

|-

|-

|If you do not have good bandwidth you can download and watch it

|If you do not have good bandwidth you can download and watch it

|-

|-

| The Spoken Tutorial Project Team

| The Spoken Tutorial Project Team

|-

|-

| Conducts workshops using spoken tutorials

| Conducts workshops using spoken tutorials

|-

|-

| Gives certificates for those who pass an online test

| Gives certificates for those who pass an online test

|-

|-

| For more details please write to contact at spoken hyphen tutorial dot org

| For more details please write to contact at spoken hyphen tutorial dot org

|-

|-

| Spoken Tutorial Project is a part of the Talk to a Teacher Project

| 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

| 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

| More information on this mission is available at http://spoken-tutorial.org/NMEICT-Intro

|-

|-

| The Library Management System has been contributed by a leading software MNC, through their Corporate Social Responsibility Programme.

| 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.

|They have also validated the content for this spoken tutorial.

|-

|-

|This is Arya Ratish from IIT Bombay signing off.

|This is Arya Ratish from IIT Bombay signing off.