Java Collection - 如何从Java中的TreeMap获取子映射

import java.util.SortedMap;
import java.util.TreeMap;

public class Main {
  public static void main(String[] args) {
    TreeMap<String, String> treeMap = new TreeMap<String, String>();

    treeMap.put("1", "One");
    treeMap.put("2", "Two");
    treeMap.put("3", "Three");
    treeMap.put("4", "Four");
    treeMap.put("5", "Five");    

    SortedMap sortedMap = treeMap.subMap("2", "5");
    System.out.println("SortedMap Contains : " + sortedMap);
  }
}