fromJson static method

Principle? fromJson(dynamic value)

Returns a new Principle instance and imports its values from value if it's a Map, null otherwise.

Implementation

// ignore: prefer_constructors_over_static_methods
static Principle? fromJson(dynamic value) {
  if (value is Map) {
    final json = value.cast<String, dynamic>();

    // Ensure that the map contains the required keys.
    // Note 1: the values aren't checked for validity beyond being non-null.
    // Note 2: this code is stripped in release mode!
    assert(() {
      requiredKeys.forEach((key) {
        assert(json.containsKey(key), 'Required key "Principle[$key]" is missing from JSON.');
        assert(json[key] != null, 'Required key "Principle[$key]" has a null value in JSON.');
      });
      return true;
    }());

    return Principle(
      change: mapValueOfType<String>(json, r'change'),
      domain: mapValueOfType<String>(json, r'domain'),
      hexagram: mapValueOfType<String>(json, r'hexagram'),
      n: mapValueOfType<int>(json, r'n'),
      name: mapValueOfType<String>(json, r'name'),
      principle: mapValueOfType<String>(json, r'principle'),
      slug: mapValueOfType<String>(json, r'slug'),
      sunTzu: mapValueOfType<String>(json, r'sunTzu'),
    );
  }
  return null;
}