java类排序

1、实现Comparator接口

public static class ComparatorImpl implements Comparator<Element>{

        @Override
        public int compare(Element o1, Element o2) {
            if(o1.unitPrice > o2.unitPrice)
                return 1;
            else if(o1.unitPrice < o2.unitPrice){
                return -1;
            }else{
                return 0;
            }
        }
        
    }

public static class Element {
        public int distance;
        public int fare;
        public float unitPrice;
    }

2、调用Collections的sort方法排序

ArrayList<Element> data = new ArrayList<Element>();

data.add(...);

//sort the data - small to big
ComparatorImpl comp = new ComparatorImpl();
Collections.sort(data, comp);