public class Book {
    private int storage;
    private String isbnNo;
    private String title;
    private static int counter = 1000;

public Book(String title, int initStorage){
    this.title = title;
    this.isbnNo = isbnNo;
    this.storage = storage;

    }
public void reclaim(int amount){
    this.storage += amount;
}
public void lend(int amount){
    if(storage > amount){
this.storage -= amount;
    }
}

public String isbnNo(){
return isbnNo;
        }
public String title(){
return title;

    }
public int storage(){
return storage;
}
public String toString(){
return "title: " + title   + "\n"+
        "isbnNo: " + isbnNo + "\n"+
        "storage: " + storage + "\n" +
        "-------------------";
        }
}




import java.util.*;

public class Library2 {
    private final ArrayList books = new ArrayList();

    public void addBook(Book b){
    books.add(b);
    }
public Book findBook(String isbnNo){

    for(int i=0 ;  i<books.size() ; i++){
    Book temp = (Book)books.get(i);

    if(temp.isbnNo()==isbnNo){
    return temp;
    }
}
    return null;
}
}






import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Gui {
    private JFrame frame = new JFrame("Budget library");
    private JPanel background, centerPanel,southPanel,menuBar;
    private JLabel l_isbnNo,l_title,l_reclaim,l_lend,l_storage;
    private JTextField tf_isbnNo, tf_title, tf_reclaim,tf_lend,tf_storage;
    private JButton b_find,b_reclaim,b_lend,b_clear,b_addBook;
    private Library2 library;
    private JMenuBar baren;
    private JMenu menu;
    private JMenuItem i_item,i_isbnNo,i_reclaim,i_lend,i_clear,i_find;
    private Book findB;




public Gui(Library2 l){
    library = l;

        background = new JPanel();
        background.setLayout(new BorderLayout());
        centerPanel = new JPanel();
           //   background.setBorder(BorderFactory.addBookLineBorder(Color.RED,9, false));

        centerPanel.setLayout((new GridLayout(5,2)));
        southPanel = new JPanel();
        southPanel.setLayout((new GridLayout(3,2)));
        l_isbnNo = new JLabel("isbnNo: ");
        l_title = new JLabel("title:");
        l_reclaim = new JLabel ("reclaim:");
        l_lend = new JLabel("lend:");
        l_storage = new JLabel("storage:");
        b_find = new JButton("FIND");
        b_reclaim = new JButton("Return");
        b_lend = new JButton("Lend");
        b_clear = new JButton("Clear");
        b_addBook = new JButton("Add book");
        southPanel.add(b_reclaim);
        southPanel.add(b_find);
        southPanel.add(b_lend);
        southPanel.add(b_clear);
        southPanel.add(b_addBook);



        tf_isbnNo= new JTextField(12);
        tf_title  = new JTextField(12);
        tf_reclaim= new JTextField(12);
        tf_lend= new JTextField(12);
        tf_storage= new JTextField(12);
           centerPanel.add(l_isbnNo);
           centerPanel.add(tf_isbnNo);
           centerPanel.add(l_title);
           centerPanel.add(tf_title);
           centerPanel.add(l_storage);
           centerPanel.add(tf_storage);
           centerPanel.add(l_reclaim);
           centerPanel.add(tf_reclaim);
           centerPanel.add(l_lend);
           centerPanel.add(tf_lend);
           background.add(centerPanel, BorderLayout.CENTER);
           background.add(southPanel, BorderLayout.SOUTH);
           frame.setContentPane(background);
           frame.pack();
           frame.setVisible(true);
           ClearHandler cl = new ClearHandler();
           FindHandler fh = new FindHandler();

           this.b_clear.addActionListener(cl);
           this.i_clear.addActionListener(cl);
           this.b_lend.addActionListener(new LD());
           this.b_reclaim.addActionListener(new RM());
           this.b_find.addActionListener(fh);
           this.i_find.addActionListener(fh);
           this.b_addBook.addActionListener(new AddBook());
           this.library = library;

}
private class ClearHandler implements ActionListener{
public void actionPerformed(ActionEvent ae){
   tf_isbnNo.setText("");
   tf_title.setText("");
   tf_reclaim.setText("");
   tf_lend.setText("");
   tf_storage.setText("");

}
    }

private class LD implements ActionListener{
    public void actionPerformed(ActionEvent ae){
        String sLend = tf_lend.getText();
        int amount = Int.parseInt(sLend);
        findB.lend(amount);
        tf_storage.setText("" + findB.storage());

    }
}
private class RM implements ActionListener{
    public void actionPerformed(ActionEvent ae){
         String sReclaim = tf_reclaim.getText();
         int amount = Int.parseInt(sReclaim);
         findB.reclaim(amount);
         tf_storage.setText("" + findB.storage());
         System.out.println("Return" + amount);
}  }
private class FindHandler implements ActionListener{
    public void actionPerformed(ActionEvent ae){
        String sIsbnNo = tf_isbnNo.getText();
        try{

        }catch (NumberFormatException nfe){
        JOptionPane.showMessageDialog(frame, "skriv in siffror som isbnNummer");

        return;}
        Book findB = library.findBook(sIsbnNo);
        if(findB!=null){
             tf_title.setText(findB.title());
             tf_storage.setText(""+findB.storage());
        }else JOptionPane.showMessageDialog(frame, "boken finns inte! ");
    }
}
private class AddBook implements ActionListener{
    public void actionPerformed(ActionEvent ae){
        System.out.println("add Book");
        String title = tf_title.getText();
        String isbnNo = tf_isbnNo.getText();
        int storage = Int.parseInt(tf_reclaim.getText());
        Book addBook = new Book(title, amount);
        tf_isbnNo.setText("" + addBook.isbnNo());
        library.addBook(addBook);
        tf_reclaim.setText("");
        tf_storage.setText("" + addBook.storage());


    }
}
}





public class LibrarySystem {

    /**
     * @param args the command line arguments
     */
       public static void main(String[] args) {

// TODO code application logic here
Book b1 = new Book ("Wikipedia Vol 1", 5);
Book b2 = new Book ("Linas lina", 2);
Book b3 = new Book ("Bortom vind och horisont", 1);

Library2 library = new Library2();


library.addBook(b1);
library.addBook(b2);
library.addBook(b3);
System.out.println(library.findBook(1001));
System.out.println(library.findBook(1002));
System.out.println(library.findBook(1003));


 Gui  gui = new Gui(library);

}  }