Java示例从HashTable设置键视图

import java.util.Enumeration;

import java.util.Hashtable;



public class Main {

   public static void main(String[] args) {

      Hashtable ht = new Hashtable();

      ht.put("1", "One");

      ht.put("2", "Two");

      ht.put("3", "Three");

      Enumeration e = ht.keys();



      while (e.hasMoreElements()) {

         System.out.println(e.nextElement());

      }

   }

}