Threads em JAVA

/*
 * ThreadA tem o bloqueio de b
 */
public class ThreadA {

    public static void main(String[] args) {
        ThreadB b = new ThreadB();
        b.start();
        synchronized(b){
            try{
                System.out.println("waiting for b to complete...");
                /*
                 * ThreadA(principal) passa a vez para o thread b???
                 */
                b.wait();
            }
            catch(InterruptedException ex){
                ex.printStackTrace();
            }
            System.out.println("total is: " + b.total);
        }
    }

}

class ThreadB extends Thread{
    int total;
    public void run(){
        synchronized(this){
            for(int i = 0; i < 100; i++){
                total += i;
            }
        }
        /*
         * Thread b notifica o Thread A (Thread principal)???
         */
        notify();
    }
    
}