private function getClassDeclaration()
    {
        return new Format(
            sprintf(
                '%sclass %s%s%s',
                $this->isAbstract ? 'abstract ' : '',
                $this->class,
                $this->getImplementOrExtendsDeclaration('extends', $this->extends),
                $this->getImplementOrExtendsDeclaration('implements', $this->implements)
            )
        );
    }