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//program to demonstrate thread synchronized keyword
/*
In this example, we have a Counter class that has a count variable and an increment() method. The increment()
method is synchronized, which means that only one thread can access it at a time.
We then create two threads, thread1 and thread2, and start them both. Each thread calls the
increment() method 1000 times.
We then use the join() method to wait for both threads to finish executing.
Finally, we print the value of the count variable.
Without synchronization, it is possible that the two threads could interleave their
execution and the value of the count variable could be incorrect. However, with synchronization,
the two threads cannot interleave their execution and the value of the count variable is always correct.
*/

class Counter {
    private int count = 0;

public synchronized void increment() {
        count++;
    }

public int getCount() {
        return count;
    }
}

public class ThreadSync {
    public static void main(String[] args) {
        Counter counter = new Counter();

Thread thread1 = new Thread(() -> {
            for (int i = 0; i < 1000; i++) {
                counter.increment();
            }
        });

Thread thread2 = new Thread(() -> {
            for (int i = 0; i < 1000; i++) {
                counter.increment();
            }
        });

thread1.start();
        thread2.start();

try {
            thread1.join();
            thread2.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

System.out.println(counter.getCount());
    }
}