java.util.HashMap.size() 方法

package com.codingdict;

import java.util.*;

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

      // create hash map
      HashMap newmap = new HashMap();      

      // populate hash map
      newmap.put(1, "tutorials");
      newmap.put(2, "point");
      newmap.put(3, "is best");

      System.out.println("Size of the map: "+ newmap.size());
   }    
}