java中实现Comparable接口实现自定义排序

 class Student implements Comparable{
     String name;
     int gpa;
     @Override
     public int compareTo(Object arg0) {
         // TODO Auto-generated method stub
         Student s = (Student)arg0;

         if(gpa == s.gpa) return name.compareTo(s.name);
         else if(gpa < s.gpa) return -1;
         else if(gpa > s.gpa) return 1;
         else return 0;

     }

 }

 class Test {
     public static void main(String[] args){
         Scanner in = new Scanner(System.in);

         int n = in.nextInt();

         Student[] s = new Student[n];

         for(int i = 0;i < n;i ++){
             s[i] = new Student();
             s[i].name = in.next();
             s[i].gpa = in.nextInt();
         }

         Arrays.sort(s);

         for (Student ss : s)
         {
             System.out.println(ss.name);
             System.out.println(ss.gpa);
         }
     }
 }