自定义反向比较器reverseSort

/**

 * 自定义反向排序比较器
 */
public class ReverseSort implements Comparator {
/**日期倒序*/
    public int compare(Object obj1, Object obj2) {
    if(obj1 instanceof BbsInformation && obj2 instanceof BbsInformation){
    BbsInformation b1 =(BbsInformation)obj1;
    BbsInformation b2 =(BbsInformation)obj2;
    if(null!=b1.getBegintime()&& null!=b2.getBegintime()){
    return -b1.getBegintime().compareTo(b2.getBegintime());
    }else{
    return 0;
    }
    }
    return 0;
    }

/**和当前日期比较
* entityDate实体类时间 
* 超时返回false
* */
public static boolean compareTime(Date entityDate){
Date nowTime= new Date();
Calendar cal = Calendar.getInstance();
cal.setTime(entityDate);
Date endDate =cal.getTime();
if(endDate.compareTo(nowTime)<0){//超时
return false;
}
return true;
}

}

使用

ReverseSort reverseSort = new ReverseSort();
reverseSort.compare(obj1, obj2);