1. @override
dynamic convertFromPrimitiveValue(value)

Converts a value to a more complex value from a primitive value according to this instance's definition.

This method takes a non-Dart representation of a value (e.g. an HTTP body or database query) and turns it into a Dart representation . How this value is computed depends on this instance's definition.

Source 

@override
dynamic convertFromPrimitiveValue(dynamic value) {
  if (value == null) {
    return null;
  }

  if (relationshipType == ManagedRelationshipType.belongsTo ||
      relationshipType == ManagedRelationshipType.hasOne) {
    if (value is! Map<String, dynamic>) {
      throw new QueryException(QueryExceptionEvent.requestFailure,
          message:
          "Expecting a Map for ${MirrorSystem.getName(destinationEntity.instanceType.simpleName)} in the '$name' field, got '$value' instead.");
    }

    ManagedObject instance = destinationEntity.instanceType
        .newInstance(new Symbol(""), []).reflectee;
    instance.readFromMap(value as Map<String, dynamic>);

    return instance;
  }

  /* else if (relationshipType == ManagedRelationshipType.hasMany) { */

  if (value is! List<Map<String, dynamic>>) {
    throw new QueryException(QueryExceptionEvent.requestFailure,
        message:
        "Expecting a List for ${MirrorSystem.getName(destinationEntity.instanceType.simpleName)} in the '$name' field, got '$value' instead.");
  }

  if (value.length > 0 && value.first is! Map) {
    throw new QueryException(QueryExceptionEvent.requestFailure,
        message:
        "Expecting a List<Map> for ${MirrorSystem.getName(destinationEntity.instanceType.simpleName)} in the '$name' field, got '$value' instead.");
  }

  return new ManagedSet.from(
      (value as List<Map<String, dynamic>>).map((v) {
        ManagedObject instance = destinationEntity.instanceType
            .newInstance(new Symbol(""), []).reflectee;
        instance.readFromMap(v);
        return instance;
      }));
}