关于java的排序规则写法

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import java.io.*;
import java.util.*;
import java.math.*;
import java.text.*;
import java.util.Comparator;
public class Main{
final static int maxn=100;

public static class student{
String name;
int score;
student(){};
student(String nn,int ss){
name=nn;
score=ss;
}
String getname(){
return name;
}
int getscore(){
return score;
}
void output(){
System.out.println(name+" "+score);
}
};

public static class MyComparator implements Comparator{
public int compare(Object  obj1, Object obj2) {
student x=(student)obj1;
student y=(student)obj2;
if(x.getscore()!=y.getscore())
return x.getscore()<y.getscore()?1:-1;
return x.getname().compareTo(y.getname())>0?1:-1;
}
};

public static student p[]=new student[maxn];
public static Integer a[]=new Integer[maxn];

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

///排序1：数组排序
//示例数据
//5
//4 1 3 6 9
int n=in.nextInt();
for(int i=0;i<n;i++)a[i]=in.nextInt();
//第1个参数传入的是数组的首地址例如a
//接下来传入的是排序的范围 x,y，表示将区间a[x]到a[y-1]段排序
//默认是从小到大排
Arrays.sort(a,0,n);
for(int i=0;i<n;i++)System.out.print(a[i]+" ");
System.out.println();
//这是构造方法类实现排序准则的形式
Arrays.sort(a,0,n,new Comparator<Integer>(){
public int compare(Integer x,Integer y){
return x<y?1:-1;//表示从大到小
}
});
for(int i=0;i<n;i++)System.out.print(a[i]+" ");
System.out.println();

//排序2：类排序
//示例数据
//5
//xiaoming 100
//dong 100
//haha 75
//hehe 80
//xiaowang 90
int m=in.nextInt();
for(int i=0;i<m;i++){
String name=in.next();
int score=in.nextInt();
p[i]=new student(name,score);
}

//示例：首先按成绩从高到底，若相同，按名字字典序
Arrays.sort(p,0,m,new Comparator<student>(){
public int compare(student x,student y){
if(x.getscore()!=y.getscore())
return x.getscore()<y.getscore()?1:-1;
return x.getname().compareTo(y.getname())>0?1:-1;
}
});

//这是外部定义比较器类的使用方法
Arrays.sort(p,0,m,new MyComparator());
for(int i=0;i<m;i++)p[i].output();

}
}