Usecase Diagram.

Usecase Diagram:

• Use case diagram is created to visualize the interaction of our system with the outside world. 
• The components of use case diagram are:

Use Case: Scenarios of the system.
Actor: Someone or something who is interacting with the system.
Relationship: Semantic link between use case and actor. The forms of relationship are:
    a. Association.
    b. Dependency.
    c. Generalization.

1) login:-
Primary Actor: Member
Secondary Actor: Librarian

Description:  

• The person who has membership in the library and can login into the system and use the services.
• All the information about members is maintained by the system.

Flow of Events:

• The member enters into the system by providing the user name and password.
• The catalog sends the details of user to librarian.
• The librarian validates the username and password is valid or not .
• Then librarian verifies the member is from staff or is a student.
• If member is not a student or staff then librarian rejects his request.
• If the member is either from staff or a student then provides with facilites provide to them.
• So that the member can access the books from library when ever She/he requires.

Precondition:-

• The person who is requesting should have membership and should be a staff or student.

Post condition:- NO.

2) View reports:-
Primary actor: member
Secondary actor: catalog

Description:

• The catalog displays the information about books, available, reservations etc and other information’s provided to the members by the catalog.

Precondition: 

• Member should be a valid user and he should logged in

Post condition: No

3) Search and browse:- 
Primary actor: member 
Secondary actor: NO
 
Description:

• The library displays the book in an order according to the subjects and the member can search or browse according to the requirements.

Flow of Events:

• The library assistant maintains the data base about the books that are available in the catalog.
• The user searches the book either by keyword or subject wise wise.
• If the book is found in the list, the user stops the search.

Precondition: 

• catalog has to have the data about the book.

Post condition: 

• member can reserve or take the book.

4) Make and remove reservation:-
Primary actor: Member
Secondary actor: Librarian
Description:

• A member can reserve a book or magazine that is not currently available so that when it is reserved or purchased by library the person is notified and can reserve a book at a particular date or remove the reservation made on a date.

Flow of Events:

• The members who have membership in the library request a book on a particular date.
• The librarian checks the book is currently available or not.
• If the book is available then librarian issues the book to the member on that date.
• If the book is not available currently then librarian reserves the specified book in account of person who requested it.
• When the book is available then librarian notifies the person who requested it and informs to the person.
• If the member wants to remove the reservation he requests the librarian  for that and then the librarian removes the reservation it is update in the catalog.

Precondition: 
A requesting person must be member of library.

Post condition: NO

5) Pay the dues:-
Primary actor: Member
Secondary actor: librarian
 
Description:

• The librarian checks the return date, if it expires S/he calculates the fines for extra dates so the member has to pay the dues.

Flow of Events:

• The librarian calculates the dues depending on the book returned date.
• If the return date exceeds the specified date then librarian calculates the fines based on exceed time then the librarian calculates the fine for extra time according to their norms.
• Then the member pays the fine depending on the calculated dues and hence member can access the other books.

Precondition: 

• The member has to exceed the time limit of retrun date.

Post condition: NO

6) Calculate dues:-
Primary actor: Librarian
Secondary actor: Member
Description:

• The library clerk checks the return date, if it expires S/he calculates the fines for extra dates and accepts from the member.

Flow of Events:

• The member returns the books to the library.
• The librarian receives the books and checks the returned date.
• If the return date does not exceeds the specified date then the takes the books and the member is capable for taking other books.
• If the return date exceeds the specified date then librarian calculates the fines based on exceed time and collects money from the member.
• When the member pays the fine then librarian gives a slip[ specifying that fine is paid and hence member can access the books.

Precondition: 

• The librarian checks for the status of a book.

Post condition: NO

7) Issue or take book:-
Primary actor: Member
Secondary actor: librarian

Description:

• Requesting for issue or take book is taking place between a member and library staff. 
• Member requests for book from the library or the book taken by the member is returned back after the return date has been completed.

Flow of Events:

• Member request a book in the library.
• Librarian checks for membership if book is available issues book to member.
• If book that is requested is not available notifies it to member.
• Librarian records the transaction of book.
• If the member  wants to return the book the  checks for return date of a book and then the returns the book  then the librarian record the transaction of book.

Precondition: 

• The person making the request must be a member of the library.

Post condition: NO.

8) Manages and validate:-
Primary Actor: librarian
Secondary Actor: member

Description:

• The librarian has the access to the information of the member so the librarian validates the member whether he is a genuine user or not and manages the membership and services provided to them.

Flow of Events:

• The librarian has the data of the members
• The member enters into the system by providing the required data
• The librarian validates the member  by comparing the data provides and the date which is stored by them so by that he comes to know the user is valid or not
• Then librarian verifies the member is from staff or is a student according to that he manages the people.

Precondition:-

• The librarian should have the details about the members and membership, reservations etc.

Post condition:- No.

9) Check reservations:-
Primary actor: librarian
Secondary actor: catalog

Description:

• A librarian check the reservation for the  book that is requested by the member if it is available on that date the librarian reserves that book for that date to the particular member so that one other user can access it.

Flow of Events:

• The librarian checks the book in the catalog that is needed by the member is currently available or not on that date.
• If the book is available then librarian issues the book to the member on that date update the catalog.
• If the book is not available currently then librarian reserves the specified book in account of person in the waiting state who requested it.
• When the book is available then librarian notifies the person who requested it and informs to the person.
• So that no other person can reserve or take that book on that particular date.

Precondition: 

• A  member has to make a request of  book on a particular date.

Post condition: NO
   
10) View reports:-
Primary actor: librarian
Secondary actor: catalog

• The catalog displays the information about books available, books needed , reservations made and details of the member  etc to the librarian

Precondition: 

• librarian should be a valid one and have access to the catalog database logged in.

Post condition: NO

11) Update catalog:- 
Primary actor: librarian
Secondary actor: catalog
Description:

• The librarian update the information about books available, books issued books return date, reservations made and details of the member etc in the catalog.

Flow of Events:

• The librarian stores  all the details and update their details if there are any changes  in the catalog.
• The librarian updates  all the  book that are newly available in the catalog.
• The librarian updates  all the  book that are issued in the catalog.
• The librarian updates  all the  book that are to be returend in the catalog.
• The librarian updates  all the  book that are made reservations  in the catalog.
• The librarian updates  all the  book that are not  available in the catalog.
• So that person can use the details provided in catalog and make the acess to the library.

Precondition: 

• There  should be a change in the previous data stored in the catalog .

Post condition: NO

12) Request for the new stock:-
Primary actor: librarian
Secondary actor: library administrator
Flow of Events: 

• The librarian places the order for the book which are not available in the library to the master librarian.

Precondition: 

• The librarian checks whether the books are available or not and whether they are needed or not.

Post condition: NO

13) Manages the librarians:-
Primary actor: library administrator
Secondary actor: librarian
Flow of Events:

• The master librarian supply the orders placed by the librarian.
• The  master librarian provides the permissions to acess the catalog to the librarian according to their norms.

Precondition: 

• The master librarian should have atleast one librarian under him.

Post condition: NO
        

=>	Introduction.
=>	Textual Analysis.
=>	Usecase Diagram.
=>	Activity Diagram.
=>	Interaction Diagram.
=>	Class Diagram.
=>	State Chart Diagram.
=>	Stimulus Response Diagram.