静态类

public static void main(String[] args){
SortedSet<Person> set = new TreeSet<Person>();
set.add(new Person(180));
set.add(new Person(175));

for(Person p : set){
System.out.println("身高: " + p.getHeight());
}
}

class Person implements Comparable<Person>{
    private int height;
    public Person(int _age){
        height = _age;
    }
    public int getHeight(){
        return this.height;
    }
    
    public void setHeight(int height){
        this.height = height;
    }
    @Override
    public int compareTo(Person o){
        return height - o.height;
    }