List集合排序

// 按照整型排序比较器

Collections.sort(list, new List2IntComparator(true));

//集合排序规则（根据什么排序）

public class List2IntComparator implements Comparator<KnowFirst> {
   private boolean reverseOrder; // 是否倒序
   public List2IntComparator(boolean reverseOrder) {
   this.reverseOrder = reverseOrder;
   }
   
   public int compare(KnowFirst arg0, KnowFirst arg1) {
   if(reverseOrder) 
   return Integer.parseInt(arg1.getKnowCode()) - Integer.parseInt(arg0.getKnowCode());
   else 
   return Integer.parseInt(arg0.getKnowCode()) - Integer.parseInt(arg1.getKnowCode());
   }
}