code: public void merge(Properties other, Set<String> toBeRemoved) {
  		if(properties == null) {
  			properties = createProperties();
  		}
  		
  		if(other != null && other.size() > 0) {
  			Set<Entry<Object, Object>> entrySet = other.entrySet();
  			for (Entry<Object, Object> entry : entrySet) {
  				properties.put(entry.getKey(),  entry.getValue());
  			}
  		}
  		
  		if(toBeRemoved != null && toBeRemoved.size() > 0) {
  			for (String key : toBeRemoved) {
  				properties.remove(key);
  			}
  			toBeRemoved.clear();
  		}
  	}
docs: Merge properties into the config.
  @param other