code: protected String getRootPropertyName(String propertyName) {
  		int location = propertyName.indexOf(PROPERTY_KEY_PREFIX);
  		return location == -1 ? propertyName : propertyName.substring(0, location);
  	}
docs: Returns the root property of an indexed property. The root property is
  the property that contains no indices.
  
  @param propertyName the name of the property.
  @return the root property.