Java notify() run before wait()?

Question

public class ThreadA {
    public static void main(String[] args){
        ThreadB b = new ThreadB();
        b.start();

        synchronized(b){
            try{
          


        

Answer 1

One of the many possible solutions for your problem is:

public class ThreadA {
  public static final CyclicBarrier barrier = new CyclicBarrier(2);

  public static void main(String[] args) {
    ThreadB b = new ThreadB();
    b.start();
    try {
      barrier.await();
      System.out.println("Total is: " + b.total);
    } catch (InterruptedException | BrokenBarrierException ex) {
    }
  }
}

class ThreadB extends Thread {
    int total;

    @Override
    public void run() {
        for (int i = 0; i < 100; i++) {
            total += i;
        }
        try {
          ThreadA.barrier.await();
        } catch (InterruptedException | BrokenBarrierException ex) {
        }
    }
}