code: public void remove(final String propertyName) {
          Preconditions.checkNotNull(propertyName);
          if (properties.containsKey(propertyName)) {
              properties.remove(propertyName);
          } else if (references.containsKey(propertyName)) {
              references.remove(propertyName);
          }
      }
docs: Remove a property or reference as a property from this bean.
  
  This operation can be useful when removing properties using "set"
  operation.
  
  @param propertyName name of the property as defined by the bean's schema.