public  void clear() 
{
            WeakHashMap.this.clear();
}

 public boolean contains(Object o) 
{
            return containsKey(o);
}

 public Iterator iterator() 
{
            return new KeyIterator();
}

 public boolean remove(Object o) 
{
            if (containsKey(o)) {
                WeakHashMap.this.remove(o);
                return true;
            }
            else
                return false;
}

 public int size() 
{
            return WeakHashMap.this.size();
}