TreeSet使用Comparator定制排序

import java.util.*;

class M
{
	int age;
	public M(int age)
	{
		this.age=age;
	}
	public String toString()
	{
		return "M的对象（age:"+age+"）";
	}
}

public class TestTreeSet 
{
	public static void main(String[] args)
	{
		TreeSet ts=new TreeSet(new Comparator()
		{
			public int compare(Object o1,Object o2)
			{
				M m1=(M)o1;
				M m2=(M)o2;
				if(m1.age>m2.age)
				{
					return -1;
				}
				else if(m1.age==m2.age)
				{
					return 0;
				}
				else
				{
					return 1;
				}
			}
		});
		ts.add(new M(5));
		ts.add(new M(-3));
		ts.add(new M(9));
		System.out.println(ts);
	}
}