Java Comparator比较器实例解析

package xixixi;
import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    int n = in.nextInt();
    Student[] arr = new Student[n];
    for(int i=0;i<n;i++)
    {
      String name = in.next();
      int num = in.nextInt();
      arr[i] = new Student(name, num);
    }
  }  
}

class Student{
  String name;
  int num;
  Student(String s,int n){
    name = s;
    num = n;
  }
  
  public String toString() {
    return name+"-"+num;
  }
}

 class NameComparator implements Comparator<Student>{
  public int compare(Student o1,Student o2)
  {
    if(o1.name.compareTo(o2.name)>0)
      return 1;
    else if(o1.name.compareTo(o2.name)<0)
      return -1;
    else 
      return o1.name.compareTo(o2.name);
  }
}