关于set无顺，处理对list排序

	/**
	 * 排序
	 * @param pl
	 * @return
	 */
	public static Collection PaiXu(List pl) {
		Collection PaiXuCollection = new ArrayList();
		Collections.sort(pl, new MyComparatorpx());
		for (Iterator it = pl.iterator(); it.hasNext();) {
			Zykclass p = (Zykclass) it.next();
			PaiXuCollection.add(p);
		}
		return PaiXuCollection;
	}

class MyComparatorpx implements Comparator {
	public int compare(Object o1, Object o2) {
		Zykclass p1 = (Zykclass) o1;
		Zykclass p2 = (Zykclass) o2;
		if (p1.getClasid() < p2.getClasid()) {
			return 1;
		} else if (p1.getClasid() == p2.getClasid()) {
			return 0;
		} else {
			return -1;
		}
	}
}

	public static void main(String args[]) {
//		Zykclass对象
		List pl = new ArrayList();
		pl.add(new Zykclass("p9", 49));
		pl.add(new Zykclass("p9", 5));
		pl.add(new Zykclass("p9", 19));

		Collection paic = PaiXu(pl);
		List list_ss=(List) paic;//转换为list
		for (Iterator it = paic.iterator(); it.hasNext();) {
			Zykclassp = (Zykclass) it.next();
			System.out.println(p.getClasid());
		}
	}