hashtable用法

 import java.util.Hashtable;
 public class HashTable {
 public static void main (String[] args)
 {
     Hashtable<String,Object> ht=new Hashtable<String,Object>();
     ht.put("xiao wang", 30);
     ht.put("zhang san", "aaa");
     ht.put("he hai", true);

     System.out.println(ht.size());
     ht.remove("zhang san");
     System.out.println(ht.size());

     System.out.println(ht.get("he hai"));
      ht.put("he hai", "hello");
      System.out.println(ht.get("he hai"));
 }
 }