进行降序排列
    Collections.sort(list, new Comparator<ResultTypeDesc>() {
      public int compare(ResultTypeDesc o1, ResultTypeDesc o2) {
        return o2.getRatio().compareTo(o1.getRatio());
      }
    });

Collections.sort(list, new Comparator<ResultTypeDesc>() {
public int compare(ResultTypeDesc o1, ResultTypeDesc o2) {
return o1.getRatio().compareTo(o2.getRatio());
   }
});

import java.util.*;

public class ComparatorResultType implements Comparator{

 public int compare(Object arg0, Object arg1) {
 ResultTypeDesc desc0=(ResultTypeDesc)arg0;
 ResultTypeDesc desc1=(ResultTypeDesc)arg1;

  //首先比较主指标，如果主指标相同，则比较次指标

 int flag=desc0.getXXX().compareTo(desc1.getXXX());
 if(flag==0){
  return desc0.getXXX2().compareTo(desc1.getXXX2());
 }else{
  return flag;
 } 
 }
}

//测试类中代码：
ComparatorResultType comparator=new ComparatorResultType();
Collections.sort(list, comparator);