java生成订单编号

package ceshi;

import java.text.SimpleDateFormat;
import java.util.Date;

public class T extends Thread{

    private static long orderNum = 0l;
    private static String date ;
    
    public static void main(String[] args) throws InterruptedException {
    	for (int i = 0; i < 10000; i++) {
			System.out.println(T.getOrderNo());
			Thread.sleep(1000);
		}
    }

    /**
     * 生成订单编号
     * @return
     */
    public static synchronized String getOrderNo() {
        String str = new SimpleDateFormat("yyMMddHHmm").format(new Date());
        if(date==null||!date.equals(str)){
        	date = str;
        	orderNum  = 0l;
        }
        orderNum ++;
        long orderNo = Long.parseLong((date)) * 10000;
        orderNo += orderNum;;
        return orderNo+"";
    }

}