java中实现Comparable接口实现自定义排序的示例

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); 
    } 
  }
}