Hello guys, i m working on a program that stores details of a book collection. Following are the things that should be there:
• Write a new class ‘book’ to represent details of special book objects. A book consists of (for example) the title, number of copies, author, (“The Davinci Code”, 5, “Brown”).
• Your class definition should include an appropriate constructor method, and methods to allow addition, updating, searching and sorting of objects.
• The class should have a method to store all the objects from the array into a file. A further method should allow the contents of a previously stored file of objects to be restored into an array.
• Create a menu of options for the programme including
o Input a new object from a keyboard
o Search for an object and print details to screen
o Edit an object
o Sort the objects
o Print all the entries so far
o Save objects to a file
o Retrieve objects from a file
o QuitNow i have done the book class in which i have the private fields, constructor, get and set methods and i have done the library class which is somewhat incomplete because i don't understand how to proceed.
Here is my book class.
import java.util.*;
public class Book {
private String title;
private int bookNo;
private String author;
private int noOfCopies;
public Book(String t,String a, int bN, int nOC)
{
title = t;
bookNo = bN;
author = a;
noOfCopies = nOC;
}
public Book()
{
title = "";
bookNo = 0;
author = "";
noOfCopies = 0;
}
//Return the title of this book
public String getTitle()
{
return title;
}
//Return the number of copies of this book
public int getNoOfCopies()
{
return noOfCopies;
}
//Return the book number of this book
public int getBookNo()
{
return bookNo;
}
//Return the author of this book
public String getAuthor()
{
return author;
}
// Set the title of this book to the given string
public void setTitle(String t)
{
title = t;
}
// Set the number of copies of this book to the given integer
public void setNoOfCopies(int nOC)
{
noOfCopies = nOC;
}
// set the book number of this book to the given integer
public void setBookNo(int b)
{
bookNo = b;
}
// set the author of this book to the given String
public void setAuthor(String a)
{
author = a;
}
/*public boolean equals(String t)
{
boolean equals = false;
if(title.equals(t)) {
equals = true;
}
return equals;
} // IGNORE THIS METHOD*/
}Following is my library class with adding, updating, searching and writing to file methods. The booksort is incomplete.
/**
* An example of a library class which holds an array of books
* and an indicator pointing to the next available slot in the array
*/
import java.io.*;
import java.util.*;
import javax.swing.JOptionPane;
public class Library
{
final int SIZE = 20;
Book[] books = new Book[SIZE]; //The array can hold maximum of 20 book records
int bookIndex = 0;
//Method to add book objects which can be called from the main method if the user wishes to add details of a book, i.e. create a new object in class book.
public void addBook()
{
Book b = new Book();
b.setTitle((JOptionPane.showInputDialog("What is the title?")));
b.setNoOfCopies((Integer.parseInt(JOptionPane.showInputDialog("What is the number of copies?"))));
b.setBookNo((Integer.parseInt(JOptionPane.showInputDialog("What is the book number?"))));
b.setAuthor((JOptionPane.showInputDialog("What is the author")));
books[bookIndex] = b;
bookIndex++;
}
//Method to update fields of a book object
public void updateBook()
{
int index = Integer.parseInt(JOptionPane.showInputDialog("Please enter the index number of the book you would like to update"));
books[index] = new Book();
books[index].setTitle(JOptionPane.showInputDialog("Enter the Title"));
books[index].setNoOfCopies(Integer.parseInt(JOptionPane.showInputDialog("Enter the number of copies?")));
books[index].setBookNo(Integer.parseInt(JOptionPane.showInputDialog("Enter the book number?")));
books[index].setAuthor(JOptionPane.showInputDialog("Enter the author?"));
}
//Method to search for an object
public static int linearSearch(Book [] data, int key, int sizeOfArray)
{
for (int counter = 0; counter < sizeOfArray; counter++)
{
if (data[counter].getBookNo() == key)
return counter; // return position where found
}
return -1; // if drop off end of array, its not there
}
//Method to write to a file
public void writeBook()throws IOException
{
String filename = JOptionPane.showInputDialog("Please enter a file name to add the book details in.");
FileWriter outputFile = new FileWriter(filename);
BufferedWriter outputBuffer = new BufferedWriter(outputFile);
PrintWriter printStream = new PrintWriter(outputBuffer);
Book temp = new Book();
temp = books[bookIndex];
printStream.println(temp.getTitle());
printStream.println(temp.getNoOfCopies());
printStream.println(temp.getBookNo());
printStream.println(temp.getAuthor());
printStream.close();
}
public void bookSort()
{
}
}AND finally this is the main class which is very much incomplete. Please help me, when i run the main class and enter the addbook details, and later when i try to search for the book just added, it gives me error. Also please tell me how to do the sort method and the rest.
import javax.swing.*;
public class Example {
public static void main(String[] args)
{
int option = 1;
System.out.println("Enter 1 to add a book");
System.out.println("Enter 2 to search for a book");
while(option!=-1)
{
String str = JOptionPane.showInputDialog("Enter an option");
option = Integer.parseInt(str);
Library pp = new Library();
switch(option)
{
case 1:
pp.addBook();
break;
case 2:
int k = Integer.parseInt(JOptionPane.showInputDialog("Enter the book number of the book to search for"));
pp.linearSearch(pp.books,k,pp.SIZE);
break;
}
}
}
}KINDLY HELP.