Java中利用比较器对一个对象的相关属性的排序

import java.util.*;

class student{
	int number;
	public int getNumber() {
		return number;
	}
	public void setNumber(int number) {
		this.number = number;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	String name;
	public student(){
		
	}
	public student(int number,String name){
		this.name=name;
		this.number=number;
	}
}
class studentCom<T> implements Comparator<T>{
	String type="";
	public studentCom(){
		
	}
	public studentCom(String type){
		this.type=type;
	}
	@Override
	public int compare(Object o1, Object o2) {
		student s1=(student)o1;
		student s2=(student)o2;
		if(type.equals("xuehao")){
			return s1.number-s2.number;//从小到大
		}else if(type.equals("xingming")){
			return s1.name.compareTo(s2.name);
		}else if(type.equals("special")){
			return s2.name.compareTo(s1.name);
		}else{
			return 0;
		}	
	}
}
public class Test1 {
	
	public static void main(String[] args) {
		String type="";//按照什么排序/学号、姓名、成绩等
		student s1=new student(92,"ggg");
		student s2=new student(99,"ggg");
		student s3=new student(90,"ggg");
		student s4=new student(100,"bbb");
		student s5=new student(32,"zzzz");
		student s6=new student(20,"hhhh");
		ArrayList<student> list =new ArrayList<student>();
		list.add(s1);
		list.add(s2);
		list.add(s3);
		list.add(s4);
		list.add(s5);
		list.add(s6);
		System.out.println("--------按照姓名排序-------");
		type="xingming";
		Collections.sort(list,new studentCom<student>(type));
		for(student ss:list){
			System.out.println(ss.name+"  "+ss.number);
		}
		System.out.println("--------按照学号排序-------");
		type="xuehao";
		Collections.sort(list,new studentCom<student>(type));
		for(student ss:list){
			System.out.println(ss.name+"  "+ss.number);
		}
	}
		
}