Java-Business-Application/C2/Issuing-and-Returning-a-book/English-timed

Time	Narration
00.00	Welcome to the spoken-tutorial on Issuing and returning a book.
00.05	In this tutorial, we will learn how to :
00.08	Fetch all the user details
00.11	To Issue a book
00.13	To return a book
00.15	Here we are using
00.17	Ubuntu Version 12.04
00.20	Netbeans IDE 7.3
00.23	JDK 1.7
00.25	Firefox web-browser 21.0
00.29	You can use any web-browser of your choice.
00.33	To follow this tutorial you must have knowledge of
00.37	Basics of Java Servlets and JSPs
00.40	Creating and viewing inventories
00.44	If not, for relevant tutorials please visit our website.
00.48	In the earlier tutorial, we had seen how the Admin Section works.
00.53	Here, in this tutorial we have added more functionalities to the Admin Section.
00.59	So, Let us switch to the browser.
01.02	Let us login again as the admin.
01.05	We can see that we have two more options in the Admin Section Page - List Users and Checkout/Return Book.
01.14	Now, let us come to the IDE.
01.18	We can see that in the adminsetion.jsp there are two more radio buttons.
01.24	One for List Users and the other for Checkout/Return Book.
01.30	Now, switch back to the browser.
01.33	We will click on the radio button for List Users.
01.38	It has all the details like First Name, Surname, Age, Gender and Username.
01.48	The steps are similar to the earlier two options.
01.51	We saw them in the previous tutorial.
01.55	Now, let us click on the next option which is to Checkout or Return Book.
02.01	We get a form which allows you to checkout as well as return book.
02.06	We will now see the code for the same.
02.09	Switch back to the IDE.
02.11	We clicked on Checkout/Return Book.
02.14	So menuselection is equal to checkoutbook
02.18	The steps are the same that we saw for List Books.
02.23	But here, we forward the request to checkOut.jsp using RequestDispatcher.
02.29	Now, let us come to checkOut dot jsp.
02.33	This page is similar to that of listBooks dot jsp.
02.38	Except that we have a radio button against each book.
02.42	So that we can Checkout/Return that book.
02.46	We also have a username field to get the username of the user who has to checkout the book.
02.53	We also have a Date field to set the return date of the book.
02.59	We set the return date as one week from current date.
03.04	This is done using the class Calendar.
03.07	The add function of this class takes two parameters.
03.13	The First is the present day of the year.
03.16	Second is the number of days to be added to the present day.
03.21	We have added seven days.
03.23	Now note that form action is equal to CheckoutServlet.
03.29	Now, let us come back to the browser.
03.32	We will now click on BookId 1.
03.35	Type the username as arya.
03.38	We see that the return date is one week from today’s date.
03.43	Note that the number of Available Copies is 9.
03.48	Click on Checkout Book.
03.51	We get the Checkout Success Page.
03.55	We will click on here to come back to Admin Section Page.
03.59	Again click on Checkout/Return Book.
04.03	We can see that the number of Available Copies reduces to 8.
04.08	We will see the code for this now.
04.10	Come back to the IDE.
04.13	Go to CheckoutServlet.java.
04.16	We have set the errorMsgs list
04.19	We have set the errorMsgs in the request.
04.23	We get the username from the request using getParameter.
04.28	Similarly we get checkout_book, return_book and book id.
04.34	Next, we parse the BookId as Integer from the Id.
04.40	We validate the username and book id.
04.44	We also validate if Checkout_book and Return_Book is null.
04.50	Then, we validate if either of them is not null.
04.55	Here, we check if the user exists in the system using userExists method.
05.01	We then store the returned value of the method in userExists variable.
05.07	Now, we will see what we do in this method.
05.11	First we execute the query to check if the username exists in the table.
05.18	Then we initialize the integer variable userExists to 0.
05.23	If the username exists then we set userExists to 1.
05.29	We then return the value of userExists.
05.33	So, if the method returns 0 then, it means the user does not exist in the system.
05.42	else, If user exists then we call bookAlreadyIssued method.
05.50	We then store the returned value of the method in bookIssued.
05.55	Here, we check if the same book has already been issued by the same user.
06.01	Now, let us come to bookAlreadyIssued method.
06.05	Here, we have set an integer variable bookAlreadyIssued to 0.
06.12	We execute the query to check if a book with the same bookid is issued by the same user.
06.18	We get bookid from Checkout table.
06.23	If BookId exists then, set the variable bookAlreadyIssued to 1.
06.30	We then return the value of bookAlreadyIssued.
06.34	So, If the method returns 1 then it means the same user has already borrowed this book.
06.43	Now, come back to the browser.
06.46	Now, Let us now try to checkout the same book by the same user.
06.51	Type the username as arya.
06.54	Click on the radio button against BookId 1.
06.59	Then click on Checkout book.
07.03	We see that we get error message that the same user has already borrowed this book.
07.10	Now, switch back to the IDE.
07.14	If userExists in the system and if the checkout_book is not null, we call checkout method.
07.22	Let us see what we do in this method.
07.25	Here, we get the availablecopies for corresponding id.
07.31	We get this from Books table.
07.35	We then store the number of availablecopies into the variable availableCopies.
07.41	We check if availableCopies is greater than 0 and bookIssued is equal to 0.
07.50	We get the dateofreturn from the request and store in the returndate.
07.56	We then, call insertIntoCheckout.
08.00	We will see what we do in insertIntoCheckout method.
08.05	Here, we store the book_id, userName and returndate into the Checkout table.
08.12	Then we call decrementAvailableCopies method.
08.16	We will see what we do in this method.
08.19	Here, we execute the query to decrement the availablecopies in the Books table by 1.
08.26	Then we call the setCheckoutIntoRequest method.
08.29	Let us come to this method.
08.32	In this method, we set the checkout attribute into the request.
08.38	Then we we forward the request to successCheckout.jsp using RequestDispatcher.
08.45	If availableCopies is 0, then we print There are no copies of the requested book available.
08.53	Now, let us come to successCheckout dot jsp.
08.58	Here, first we get the checkout attribute from the request.
09.03	We then, display the success message for successful Checkout.
09.08	You can try out the different errors by yourself.
09.11	Now, let us return the book. So switch to the browser
09.15	Click on bookId 1 and type the username as arya.
09.21	Then, click on Return book.
09.24	We get the success message that book has been successfully returned.
09.29	Click on here for another checkout/return.
09.33	So, we come back to Admin Section Page.
09.36	Click on Checkout/Return Book.
09.39	We can see that the number of available copies has been incremented.
09.45	We will see the code for this.
09.47	Come back to the IDE.
09.49	Open CheckoutServlet dot java.
09.53	We check if userExists is equal to 1 and return_book is not equal to null.
10.00	Then we call returnBook method.
10.03	Let us come to this method.
10.06	Here, we select the totalcopies and availablecopies from Books table for the book id.
10.14	We store the totalcopies and availablecopies to totcopies and availcopies.
10.21	Then we check if available copies exceed the totalcopies.
10.27	Let us come back to the browser.
10.30	Let us now return a book for a user who has not borrowed the book.
10.35	Type the username as mdhusein.
10.39	Click on book id 1.
10.42	Then click on Return Book.
10.44	We can see that we get the error message The given user has not borrowed this book!!
10.50	Now, come back to the IDE.
10.53	Here, we check if bookIssued is equal to 1.
10.57	We then call removeFromCheckout method.
11.01	Let us come to this method.
11.04	Here, we execute the query to delete from Checkout table the entry which has returned the book.
11.14	Then, we call incrementAvailableCopies method.
11.18	Let us come to this method.
11.21	Here, we increment the availablecopies by 1.
11.25	We execute the query to update in the Books table.
11.29	Then we call the setReturnIntoRequest method.
11.34	Let us come to this method.
11.37	Here, we set the returnBook attribute into the request.
11.41	Then we forward to successReturn page using RequestDispatcher.
11.48	The successReturn page is similar to that we had for successCheckout page.
11.53	Now, come back to the browser. Come back to the login page.
11.58	We can see that we have a link called Visitor’s Home Page.
12.03	We can see that we get a list of all the books available.
12.07	So, In this tutorial we have learnt:
12.10	To list all the users
12.12	To fetch a book
12.13	To return a book.
12.15	To know more about spoken tutorial project, watch the video available at the following link.
12.20	It summarizes the Spoken Tutorial Project
12.24	If you do not have good bandwidth you can download and watch it
12.28	The Spoken Tutorial Project Team
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12.32	Gives certificates to those who pass an online test
12.36	For more details please write to contact at spoken hyphen tutorial dot org
12.41	Spoken Tutorial Project is a part of the Talk to a Teacher Project
12.44	It is supported by the National Mission on Education through ICT, MHRD, Government of India
12.50	More information on this mission is available at
12.52	http://spoken-tutorial.org/NMEICT-Intro
12.58	The Library Management System has been contributed by a leading software MNC, through their Corporate Social Responsibility Programme.
13.06	They have also validated the content for this spoken tutorial.
13.10	This is Arya Ratish from IIT Bombay signing off. Thank you for joining.

Contributors and Content Editors

PoojaMoolya, Pratik kamble, Sandhya.np14