Java Collection - 如何将HashMap转换为TreeMap，以通过键对键值对进行排序

import java.util.HashMap;
import java.util.Map;
import java.util.TreeMap;

public class Main {

  public static void main(String[] a) {
    Map<String, String> yourMap = new HashMap<String, String>();
    yourMap.put("1", "one");
    yourMap.put("2", "two");
    yourMap.put("3", "three");

    Map<String, String> sortedMap = new TreeMap<String, String>(yourMap);

    System.out.println(sortedMap);
  }
}