LIST按某个属性值排序。List里面是…

class ComparatorList implements Comparator{

String order;//需要排序的key名

int aORd;//可以决定是升级还是降序，用正负数区分

public ComparatorList(String orderby,int aORd){

this.order=orderby;

this.aORd=aORd!=0?aORd:1;

}

@Override

public int compare(Object o1, Object o2) {

Map l1=(Map)o1;

Map l2=(Map)o2;

try {

if(order.equals("createTime")){

returnl1.get(this.order).toString().compareTo(l2.get(this.order).toString())*this.aORd;

}else{

return(int)((Long)(l1.get(order)!=null?l1.get(order):0l)-(Long)(l2.get(order)!=null?l2.get(order):0l))*aORd;

}

} catch (NullPointerException e) {

return 0;

}

}

}

Collections.sort(l1, newComparatorList("createTime",-1));