Java에서 모든 TreeSet 요소 삭제

import java.util.HashSet; 
import java.util.TreeSet; 
import java.util.Set; 

public class TreeSet_clear{ 
 
 public static void main(String[] args) {

 Set treeset = new TreeSet(); 

 treeset.add("느릅나무1"); 
 treeset.add("느릅나무2"); 
 treeset.add("느릅나무3"); 
 
 System.out.println("이전: "+ 트리셋); 

 treeset.clear(); 
 
 System.out.println("이후: " + 트리셋); 
 }
}

before: [E2, E1, E3]
after: []