OO ECommerce

Database

All the information is stored in commaseparated files:

• Usernames: all the usernames of Registered Users are stored in the file Users.txt.
• Items: All books, ebooks, CDs, and MP3 information are stored in Books.txt, Ebooks.txt , CDs.txt, and MP3.txt , respectively (all case sensitive). Books and ebooks details are: S.No, name of the book, author, price, quantity in Store. CD and MP3 details are: S.No, name of the audio, artist, price, quantity in Store and type (CD or MP3).
• Shopping cart: The content of the shopping cart is stored in Cart[username].txt with the following fields (S.No, product name, date added, quantity).

See figure. Users.txt, Cart.txt, Books.txt, Ebooks.txt, CDs.txt, and MP3.txt

User Interface

• The execution starts with the login page (P1). If a Username already exists in Users.txt, upon signing in, access is granted and the system prints this message Hello Mr.[Username] and goes to P5. Otherwise, it prints No Access and goes back to P1. P1, P2, P3, and P4
• After Sign In, the following options are displayed (P5). If option 1 is chosen, item categories are listed (P6). If option 2 is chosen, the details of the shopping cart from Cart[username].txt is listed (P7) and for Option 3, redirect to Sign In page (P1).
• From P6, the following list of options is displayed under View Items By Category. If option 1 is chosen, list all Readables with details (P8). For option 2, list all Audio products (similar to P8). For option 1, the control goes to the previous page (P5).
• From P8, if option 1 or 2 is chosen, you will get the user input on the id of the item and the quantity and print a message saying the selected items have been added to the cart. If the requested quantity is not available, an appropriate message should be printed. If the User prefers to continue shopping, redirect to P6 or else go to Checkout.
• Each time an item is purchased, quantity is deducted and the new quantity is stored in the corresponding .txt file.
• In the Check out (P10), add the list of items in the Cart, apply HST(13%) for every item, Environment tax (2% on each time), and Shipping (10%) for CDs and Books only on each item purchased.
• After prompting the user to check if he wants to pay, print the Confirmation Id (Starting with U1000) and print the name of the person to which the item is shipped and go to the Browse item page. P3, P5, and P7 P6, P9, and P8
• If option 0 is chosen go to P10 else if 2 is chosen redirect to P6 P10
• Ignore case sensitivity i.e. Yes, yes, YES, YeS, yeS, No, no, nO, etc should all be valid forms of accepting payment.

OO Design

• Your implementation should follow the following structure of classes. You may add new methods to have a better level of modularity.

public abstract class Item{
public abstract String getInfo(...);
public abstract int getPrice(...);

protected int price;
protected int sNo; /

/ Add other fields if necessary
}

public class Readable extends Item {
protected String authorName;
public String getInfo(...){...} //Returns sNo, Name, Author name, etc in a string

@Override
public int getPrice(...){ // override
…
}
}

public class Book extends Readable {
…

@Override
public int getPrice(...){ // override to get the item price and add 2% (Environment Tax)
…
}
}

public class eBook extends Readable{

@Override
public int getPrice(...){ // override and only call the parent’s constructor to get the base price.
…
}

public class Audio extends Item {

protected String artistName;

public String getInfo(...){...} //Returns sNo, Name, Artist name, etc in a string

@Override
public int getPrice(...){ // override
…
…
}

public class CD extends Audio {
…

@Override
public int getPrice(...){ // override to get the item price and add 2% (Environment Tax)
…
}
}

public class MP3 extends Audio{
@Override
public int getPrice(...){ // override and only call the parent’s getPrice() to get the base price.
…
}

public class User{
private String username;
public String getUsername(...){ // stores the username.
…
}

public class ShoppingCart extends User {
private content //array of items

public String getContent(...){// return the content of the shopping cart
public addItem (...){}
}

public class UserInterface{
private array readables;
private array audioProducts;
private int currentPage; // the page number (P1..P10)

public int getCurrentPage(...){ // This method is for page navigation. Based on the values of the state variable, call different pages

public int changeCurrentPage(...){ // This method is for page navigation. It should change to current page and show the content.

public void getReadables(); // Fetches all readables from the files and places them in the readables array

public void getAudioProducts(); // Fetches all audio products from the files and places them in the readables array

public void showReadables(); // Displays all readables for browsing

public void showAudioProducts(); // Displays all audio products for browsing
…
}