code: public void setProperty(T property, String value) throws IllegalArgumentException
      {
          if (value == null)
          {
              throw new IllegalArgumentException("Cannot set a null value, use reset instead");
          }
  
          String propertyName = getTranslator().getPropertyName(property);
          if (properties.setProperty(propertyName, value))
          {
              firePropertyChanged(property);
          }
      }
docs: Set the given property using a string. This will not write the new value
  to the file system.
  
  @see #saveProperty(Object, String)
  
  @param property
  the property whose value is being set
  @param value
  the value to set
  @throws IllegalArgumentException
  if a <code>null</code> value is given (see
  {@link #resetProperty(Object)})