code: public boolean has(String key){
  		LazyNode child=root.child;
  		while(child!=null){
  			if(keyMatch(key,child)){
  				return true;
  			}
  			child=child.next;
  		}
  		return false;
  	}
docs: Returns true if the given key matches a field on this object.
  
  @param key the name of the field to look for
  @return true if the key exists, false otherwise