关于synchronized有趣的同步问题

public class SyncThreadTest extends Thread {  public static Integer count = 0;  private static final int TIMES = 10000;  public SyncThreadTest(){    super("SyncThread");  }  @Override  public void run(){    synchronized (count){      for (int i = 0; i < TIMES; i ++){        count++;      }    }  }  public static void main(String[] args) throws InterruptedException{    SyncThreadTest t1 = new SyncThreadTest();    SyncThreadTest t2 = new SyncThreadTest();    t1.start();    t2.start();    t1.join();    t2.join();    System.out.println(count);  }}