简单实现多线程同步示例（模拟购票系统）

      以下内容为实现多线程同步过程，模拟购票系统进行同步购买情况；该处并未考虑线程守护问题，后期将对线程锁等安全问题进行初步研究！

1、class：Main2

package cn.com.chysoft.demo2;
/**
  * 多线程模拟购票系统
  * 
  * @author chenyong QQ:369232566
  * @date 2013-03-21 下午14:10
  */
  public class main2 {

  /**
  * 多线程共享
  * 
  *@param args
  */
  public static void main(String[] args)   {
// TODO Auto-generated method stb
TicketCentre centre = new TicketCen  tre(10);// 初始化票务中心的票数

Instance instance1 = new Instance(200000, new Ticket(1, "张三", centre));
Instance instance2 = new Instance(800000, new Ticket(2, "王八", centre));
Instance instance3 = new Instance(400000, new Ticket(3, "狗子", centre));
Instance instance4 = new Instance(500000, new Ticket(1, "学妹", centre));
Instance instance5 = new Instance(300000, new Ticket(3, "李五哥", centre));
Instance instance6 = new Instance(100000, new Ticket(1, "习哥", centre));

Thread t1 = new Thread(instance1, "南站（1号窗口）");
Thread t2 = new Thread(instance2, "客运中心（2A号窗口）");
Thread t3 = new Thread(instance3, "南站（2号窗口）");
Thread t4 = new Thread(instance4, "南站（2号窗口）");
Thread t5 = new Thread(instance5, "南站（1号窗口）");
Thread t6 = new Thread(instance6, "客运中心（1B号窗口）");


t1.start();
t2.start();
t3.start();
t4.start();
t5.start();
t6.start();
}
}

//====================================================================================================================

2、多线程实现类 Instance 

package cn.com.chysoft.demo2;

import java.text.SimpleDateFormat;

/**
 * 线程实现
 * 
 * @author chenyong QQ:369232566
 * @date 2013-03-21 下午14:14
 */
public class Instance implements Runnable {
	private Ticket ticket;
	private boolean isOk;// 是否购票成功
	private TicketCentre centre;// 票务中心
	private int wtime;// 购票耗时

	public Instance(int wtime, Ticket ticket) {
		this.wtime = wtime;
		this.ticket = ticket;
	}

	private final void fun(int wtime) {
		this.centre = ticket.getCentre();
		try {
			this.isOk = this.centre.buy(this.ticket);// 购买
			/**
			 * 设置余票，因为对象中的数值是共享的
			 */
			this.showMessage(this.ticket.getCentre().getSurplus());
			Thread.sleep(wtime);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
	}

	public void showMessage(int current) {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss:SSSSSSS --> ");
		StringBuffer sbCtx = new StringBuffer(sdf.format(this.ticket.getTime().getTime()));
		sbCtx.append(this.ticket.getUser());
		if (this.isOk) {
			sbCtx.append(" 在 ").append(Thread.currentThread().getName()).append(" 购买 ").append(this.ticket.getNum()).append(" 张票, 当前剩余 ").append(current).append(" 张。");
		} else {
			sbCtx.append(" 在 ").append(Thread.currentThread().getName()).append(" 购买失败！").append("剩余 ").append(current).append(" 张。");
		}
		System.out.println(sbCtx);
	}

	public void run() {
		this.fun(this.wtime);
	}

}

//====================================================================================================================

3、车票基本信息

package cn.com.chysoft.demo2;

import java.util.Date;

/**
 * 购票信息
 * 
 * @author chenyong QQ:369232566
 * @date 2013-03-21 下午14:14
 */
public class Ticket {
	private String user;// 购买人
	private int num;// 购票数量
	private Date time;// 购票时间
	private TicketCentre centre;// 购票中心

	/**
	 * 初始化车票信息
	 * 
	 * @param num
	 * @param user
	 * @param centre
	 */
	public Ticket(int num, String user, TicketCentre centre) {
		this.num = num;
		this.user = user;
		this.centre = centre;
	}

	public String getUser() {
		return user;
	}

	public void setUser(String user) {
		this.user = user;
	}

	public int getNum() {
		return num;
	}

	public void setNum(int num) {
		this.num = num;
	}

	public void setTime(Date time) {
		this.time = time;
	}

	public Date getTime() {
		return time;
	}

	public TicketCentre getCentre() {
		return centre;
	}

	public void setCentre(TicketCentre centre) {
		this.centre = centre;
	}
}

//====================================================================================================================

4、票务中心处理

package cn.com.chysoft.demo2;

import java.util.Date;

/**
 * 购票中心
 * 
 * @author chenyong QQ:369232566
 * @date 2013-03-21 下午14:01
 */
public class TicketCentre {
	private int tatol = 0;// 车站票数
	private int current = 0;// 当前剩余票数
	private boolean flag = false;// 是否购完

	/**
	 * 初始化总票值
	 * 
	 * @param tatol
	 */
	public TicketCentre(int tatol) {
		this.tatol = this.current = tatol;
	}

	/**
	 * 购票
	 * 
	 * @param ticket
	 * @return
	 */
	public synchronized boolean buy(Ticket ticket) {
		ticket.setTime(new Date());
		if (!this.getFlag()) {// 还有余票
			this.current = this.current - ticket.getNum();
			if (this.current >= 0) {
				if (this.current == 0) {// 当前已无票
					this.flag = true;
				}
				return true;
			} else {
				// 购买票数多于余票
				this.current = this.current + ticket.getNum();
			}
		}
		return false;
	}

	/**
	 * 余票查询
	 * 
	 * @return
	 */
	public int getSurplus() {
		return this.current;
	}

	public int getTatol() {
		return tatol;
	}

	public int getCurrent() {
		return current;
	}

	public boolean getFlag() {
		return flag;
	}
}

输出结果如下，因线程调度顺序和结果不一：