多线程(三)——多线程安全问题之同步代码块（Synchronized）

class Ticket implements Runnable
{
	private int tick = 100000;
	Object obj = new Object();
	public void run()
	{
		while(true)
		{
			synchronized(obj)
			{
				if(tick>0)
				{
					try{Thread.sleep(1);}
					catch(Exception e){}
					System.out.println(Thread.currentThread().getName()+"------sale:"+tick--);
				}
			}
		}
	}
}

class TicketDemo4
{
	public static void main(String[] args)
	{
		Ticket t = new Ticket();
		Thread t1 = new Thread(t);
		Thread t2 = new Thread(t);
		Thread t3 = new Thread(t);
		Thread t4 = new Thread(t);
		t1.start();
		t2.start();
		t3.start();
		t4.start();
	}
}