r = $r; $this->g = $g; $this->b = $b; } public function getR(): int { return $this->r; } public function getG(): int { return $this->g; } public function getB(): int { return $this->b; } public static function createFromArray(array $data): self { foreach (['r', 'g', 'b'] as $key) { Assertion::keyExists($data, $key, sprintf('The key "%s" is missing', $key)); Assertion::integer($data[$key], sprintf('The key "%s" is invalid', $key)); } return new self( $data['r'], $data['g'], $data['b'] ); } public function jsonSerialize(): array { return [ 'r' => $this->r, 'g' => $this->g, 'b' => $this->b, ]; } }