下面程序运行的结果是 。public class E {public static void main(String args[]) {Bank b=new Bank();b.thread1.start();b.thread2.start();}}class Bank implements Runnable {Thread thread1,thread2;Bank() {thread1=new Thread(this);thread2=new Thread(this);thread1.setName("A");thread2.setName("B");}public void run() {printMess();}public void printMess() {synchronized(this) { //当一个线程使用同步块时，其他线程必须等待System.out.println(Thread.currentThread().getName()+"正在使用这个方法");try { Thread.sleep(2000);}catch(Exception exp){}System.out.println(Thread.currentThread().getName()+"正在使用这个同步块");}}}