40 lines
1.5 KiB
Java
40 lines
1.5 KiB
Java
import java.util.concurrent.*;
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import java.util.*;
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class SeatAlreadyBookedException extends Exception {
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SeatAlreadyBookedException(String msg) { super(msg); }
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}
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public class SeminarHall {
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static final int TOTAL_SEATS = 15;
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static Map<Integer, String> seats = new ConcurrentHashMap<>();
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public static void main(String[] args) {
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ExecutorService executor = Executors.newFixedThreadPool(20);
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for (int i = 1; i <= 15; i++) seats.put(i, "Available");
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for (int i = 0; i < 20; i++) {
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int userId = i;
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executor.submit(() -> {
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try {
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bookSeat(userId, "User" + userId, "Aadhar" + userId);
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} catch (SeatAlreadyBookedException e) {
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System.out.println(e.getMessage());
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}
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});
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}
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executor.shutdown();
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try { executor.awaitTermination(1, TimeUnit.MINUTES); } catch (InterruptedException e) {}
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System.out.println("Final Booking Status: " + seats);
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}
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static void bookSeat(int userId, String name, String aadhar) throws SeatAlreadyBookedException {
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int seatNumber = (userId % TOTAL_SEATS) + 1;
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synchronized (seats) {
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if (!seats.get(seatNumber).equals("Available")) {
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throw new SeatAlreadyBookedException("Seat " + seatNumber + " already booked by another user.");
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}
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seats.put(seatNumber, name + " (" + aadhar + ")");
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System.out.println("Seat " + seatNumber + " booked by " + name);
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}
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}
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}
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