code: public void setProperty(final String propertyName, final String value) {
          Preconditions.checkNotNull(propertyName);
          if (value == null) {
              properties.put(propertyName, null);
              return;
          }
          List<String> values = new ArrayList<>();
          values.add(value);
          properties.put(propertyName, values);
      }
docs: Overwrite the current values with the provided value.
  
  @param propertyName name of the property as defined by the bean's schema.
  @param value final String representations of the property that conforms to
  its type as defined by the bean's schema.