排序：这个坑，你要注意：Comparison method violates its general contract!

解决方法如下：

/**
	 * 对比类：根据持有金额
	 */
	private static class  TenderCollectComparator implements Comparator {
 
		public int compare(TenderCollect b1, TenderCollect b2) {
 
			return b1.getTocollectmoney().compareTo(b2.getTocollectmoney());
		}
	}

参考 https://blog.csdn.net/xvshu/article/details/70153759