code: public static String getValue(String propertyName, String instanceName) {
          return getPropertyService().getValue(propertyName, instanceName);
      }
docs: Returns a property value as a string.
  
  @param propertyName Name of the property whose value is sought.
  @param instanceName An optional instance name. Use null to indicate the default instance.
  @return The property value, or null if not found.
  @see IPropertyService#getValue