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Java

Java Help

Using Java.

  1. Write class, Publisher, with attributes name and state.

  2. Write Book class with attributes, title, author, isbn, publisher, and price. Book class has method calculateCharge that accepts the quantity sold and returns the total charge.

  3. Write two children of Book: Fiction and NonFiction. Fiction has attribute fiction code. NonFiction has attribute category code.

  4. Data will be in a two-dimensional data array as follows:

Fiction, Abraham Lincoln Vampire Hunter, Grahame-Smith, Wiley, NY, 978-0446563079, 13.99, 222

Fiction, Frankenstein, Shelley, Prescott, GA, 978-0486282114, 7.99, 321

NonFiction, Life of Kennedy, Jones, Pearson, MT, 758-29304566, 12.90, biography

Fiction, Dracula, Stoker, Addison, CA, 978-0486411095, 5.99, 145

Fiction, Curse of the Wolfman, Hageman, Wesley, MA, B00381AKHG, 10.59, 876

NonFiction, How to Pass Java, Willis, Wiley, NY, 444-395869790, 1.99, technology

Fiction, The Mummy, Rice, Addision, CA, 978-0345369949, 7.99, 954

NonFiction, History of Texas, Smith, Prescott, CA, 123-683947687, 9.75, history

  1. Rewrite the test case to create all books and calculate the charge and print out as before.

The quantity will be in a one-dimensional array as follows.

12 8 3 53 7 23 14 5 6.

Using the data array, create instances of books and store them in a one-dimensional array of Book, bookArray. Using the quantity array, walk through the book array and calculate the total charge per book sold. Print in a dialog box the book title, the book isbn, and the total charge for each book. Then, print the grand total of all books sold.

This is what I have so far.

public class Publisher { private String name; private String state;

public Publisher()
{
    setName("");
    setState("");
}

public Publisher(String name, String state)
{
    setName(name);
    setState(state);
}

public void setName(String name)
{
    this.name = name;
}

public void setState(String state)
{
    this.state = state;
}

public String getName()
{
    return name;
}

public String getState()
{
    return state;
}

public String toString()
{
    return (" Name " + name + " State " + state);
}

}


public class Book { private String title; private String author; private Publisher publisher; private String isbn; private double price;

public Book()
{
    setTitle("");
    setAuthor("");
    setPublisher(new Publisher());
    setIsbn("");
    setPrice(0.0);
}

public Book(String title, String author, Publisher publisher, String isbn, double price)
{
    setTitle(title);
    setAuthor(author);
    setPublisher(publisher);
    setIsbn(isbn);
    setPrice(price);
}

public void setTitle(String title)
{
    this.title = title;
}

public void setAuthor(String author)
{
    this.author = author;
}

public void setPublisher(Publisher publisher)
{
    this.publisher = publisher;
}

public void setIsbn(String isbn)
{
    this.isbn = isbn;
}

public void setPrice(double price)
{
    this.price = price;
}

public String getTitle()
{
    return title;
}

public String getAuthor()
{
    return author;
}

public Publisher getPublisher()
{
    return publisher;
}

public String getIsbn()
{
    return isbn;
}


public double getPrice()
{
    return price;
}

public double calculateCharge()
{
    int quantity = 0;
    return(quantity * price);


    //double charge;        
    //charge = super.calculateCharge();
    //return charge * 1.1;
}

public String toString()
{
    return(" Title " + title + " Author " + author + " Publisher " + publisher + " Isbn " + isbn + " Price " + price);
} 

}


public class Fiction extends Book { private String fictioncode;

public Fiction()
{
    super();
    setFictioncode("");
}

public Fiction(String fictioncode, String title, String author, Publisher publisher, String isbn, double price)
{
    super(title, author, publisher, isbn, price);
    setFictioncode(fictioncode);
}

public void setFictioncode(String fictioncode)
{
    this.fictioncode = fictioncode;
}

public String getFictioncode()
{
    return fictioncode;
}

public String toString()
{
    return(super.toString() + " Fiction Code " + fictioncode);
}

}


public class NonFiction extends Book { private String categorycode;

public NonFiction()
{
    super();
    setCategorycode("");
}

public NonFiction(String categorycode, String title, String author, Publisher publisher, String isbn, double price)
{
    super(title, author, publisher, isbn, price);
    setCategorycode(categorycode);
}

public void setCategorycode(String categorycode)
{
    this.categorycode = categorycode;
}

public String getCategorycode()
{
    return categorycode;
}

public String toString()
{
    return(super.toString() + " Category Code " + categorycode);
}

}


import javax.swing.JOptionPane;

public class BookTest { public static void main(String args[]) { String dataArray [][] = {{"Fiction", "AbrahamLincolnVampireHunter","Grahame-Smith","Wiley", "NY", "978-0446563079", "13.99", "222"}, {"Fiction", "Frankenstein", "Shelley", "Prescott", "GA", "978-0486282114", "7.99","321"}, {"NonFiction", "LifeofKennedy","Jones","Pearson","MT","758-29304566","12.90","biography"}, {"Fiction","Dracula","Stoker","Addison","CA","978-0486411095","5.99","145"}, {"Fiction","CurseoftheWolfman","Hageman","Wesley","MA","B00381AKHG","10.59","876"}, {"NonFiction","HowtoPassJava","Willis","Wiley","NY","444-395869790","1.99","technology"}, {"Fiction","TheMummy","Rice","Addison","CA","978-0345369949","7.99","954"}, {"NonFiction","HistoryofTexas","Smith","Prescott","CA","123-683947687","9.75","history"}};

    Book bookArray[] = new Book[8];

    String message = "Books are";

    for (int i = 0; i < bookArray.length; i++)
    {
        if (dataArray[i][0].equals("Fiction"))
        {
            bookArray[i] = new Fiction(dataArray[i][1], dataArray[i][2],
            dataArray[i][3], new Publisher(dataArray[i][4]), dataArray[i][5], Double.parseDouble(dataArray[i][6]), Integer.parseInt(dataArray[i][7]));
        }

        else 
        {
            bookArray[i] = new NonFiction(dataArray[i][1], dataArray[i][2],
            dataArray[i][3], new Publisher(dataArray[i][4]), dataArray[i][5], Double.parseDouble(dataArray[i][6]), dataArray[i][7]);
        }
    }

    for(Book b:bookArray)
    {
        message +=String.format(" %s ", b.getTitle());

    }

    JOptionPane.showMessageDialog(null, message);
}

}

1 Answer

Laurens,

The first problem is that the order of the fields in your constructors is not the same as the order of the fields in your data. You have fictionCode and categoryCode as the first fields in Fiction and NonFiction constructors, but the last fields in your data. So you need to put them last in the constructors:

   public Fiction(String title, String author, Publisher publisher, String isbn, double price, String fictioncode)
   {
       super(title, author, publisher, isbn, price);
       setFictioncode(fictioncode);
   }
   public NonFiction(String title, String author, Publisher publisher, String isbn, double price, String categorycode)
   {
       super(title, author, publisher, isbn, price);
       setCategorycode(categorycode);
   }

The second issue is that for Fiction you have defined fictionCode as a String, your constructor expects a String, and your data has it as a String, but you were trying to turn it into an int using parseInt() in BookTest when you constructor a new Fiction. So I replaced Integer.parseInt(dataArray[i][7]) with dataArray[i][7]. If you really want to make it an int you will need to change your data, the type of the private instance variable, your constructor, etc.

The third problem is the way you are trying to create Publisher objects in BookTest. Here's an alternative that will compile:

    for (int i = 0; i < bookArray.length; i++)
    {
        if (dataArray[i][0].equals("Fiction"))
        {
            Publisher p = new Publisher(dataArray[i][3], dataArray[i][4]);
            bookArray[i] = new Fiction(dataArray[i][1], dataArray[i][2], 
            p, dataArray[i][5], Double.parseDouble(dataArray[i][6]), dataArray[i][7]);
        }

        else 
        {
            Publisher p = new Publisher(dataArray[i][3], dataArray[i][4]);
            bookArray[i] = new NonFiction(dataArray[i][1], dataArray[i][2],
            p, dataArray[i][5], Double.parseDouble(dataArray[i][6]), dataArray[i][7]);
        }
    }

What this does is construct the publisher objects first, and then it uses that constructed object in the constructors for Fiction and NonFiction.

With these changes you code will now compile.