Java End Term: 22 December 2024, Set QDD3 (September 2024 term)

11. class Fridge {
22.    public final void cool() {
33.        System.out.println("Cools the fridge");
44.    }
55. }
66. class Compressor {
77.    public final void start() {
88.        System.out.println("Starts compressor");
99.    }
1010. }
1111. class DoubleDoorFridge extends Fridge, Compressor {
1212.    public void cool() {
1313.        System.out.println("Cools the double door fridge");
1414.    }
1515. }
1616. public class Test {
1717.    public static void main(String[] args) {
1818.        DoubleDoorFridge f1 = new Fridge();
1919.        DoubleDoorFridge f2 = new Compressor();
2020.    }
2121.}

1package week12;
2
3import java.awt.*;
4import javax.swing.*;
5import java.awt.event.*;
6class ButtonDemo extends JFrame implements ActionListener {
7    JButton btnGo, btnWait;
8    JLabel label;
9    JPanel p1, p2;
10    public ButtonDemo() {
11        p1 = new JPanel();
12        p2 = new JPanel();
13
14        btnGo = new JButton("Go");
15        btnWait = new JButton("Wait");
16        label = new JLabel("Click a button");
17
18        p1.add(btnGo);
19        p1.add(btnWait);
20        p2.add(label);
21
22        add(p1,"Center");
23        add(p2,"South");
24
25        btnGo.setActionCommand("Go");
26        btnWait.setActionCommand("Wait");
27        btnGo.addActionListener(this);
28        btnWait.addActionListener(this);
29        setSize(300, 150);
30        setVisible(true);
31    }
32    public void actionPerformed(ActionEvent e) {
33        //CODE SEGMENT
34    }
35}
36public class GUITest {
37    public static void main(String[] args) {
38        new ButtonDemo();
39    }
40}

1import java.util.concurrent.locks.ReentrantLock;
2class Hotel {
3    int roomsAvailable = 5;
4    private final ReentrantLock lock = new ReentrantLock();
5
6    public void bookRoom(String cN, int rR) {
7        lock.lock();
8        try {
9            if (roomsAvailable >= rR) {
10                roomsAvailable -= rR;
11                System.out.println(cN + " successfully booked " + rR + "
12                            rooms.");
13            } else {
14                System.out.println(cN + " cannot book " + rR + " rooms.");
15            }
16        } finally {
17            lock.unlock();
18        }
19    }
20}
21class HotelGuest implements Runnable {
22    Hotel hotel;
23    String customerName;
24    int roomsRequested;
25    // Constructor is defined here
26    public void run() {
27        hotel.bookRoom(customerName, roomsRequested);
28    }
29}
30public class HotelBooking {
31    public static void main(String[] args) throws InterruptedException {
32        Hotel hotel = new Hotel();
33        HotelGuest g1 = new HotelGuest(hotel, "Kiran", 3);
34        HotelGuest g2 = new HotelGuest(hotel, "Ameen", 4);
35        Thread t1 = new Thread(g1);
36        Thread t2 = new Thread(g2);
37        t1.start();
38        t2.start();
39    }
40}