class QOneThread implements Runnable{
    private int f[] = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17};
    public QOneThread(){ }
    public synchronized void run(){
        for(int j = 0; j < f.length; j++)
               System.out.print(f[j] +"  ");
        System.out.println();
    }
}
class QuestionOne{
    public static void main(String args[]){
        new Thread(new QOneThread()).start();
        new Thread(new QOneThread()).start();
    }
}

你起动的是两个线程,并且两个线程的Runnable对象都是各自独立的,所以看不出两个线程同步的现象