java.util.WeakHashMap.containsValue() 方法

package com.codingdict;

import java.util.Map;
import java.util.WeakHashMap;

public class WeakHashMapDemo {
   public static void main(String[] args) {
      Map<String, String> weakHashMap = new WeakHashMap<String, String>();

      // put keys and values in the Map      
      weakHashMap.put("1", "first");
      weakHashMap.put("2", "two");
      weakHashMap.put("3", "three");

      // check existence of value "three"
      System.out.println("Checking value 'three'");
      System.out.println(weakHashMap.containsValue("three"));
   }    
}