PHP \DesignPatterns\Behavioral\Specification\AndSpecification \DesignPatterns\Behavioral\Specification\OrSpecification \DesignPatterns\Behavioral\Specification\PriceSpecification \DesignPatterns\Behavioral\Specification\NotSpecification \DesignPatterns\Behavioral\Specification\Item \DesignPatterns\Behavioral\Specification\AndSpecification \DesignPatterns\Behavioral\Specification\SpecificationInterface \DesignPatterns\Behavioral\Specification\AndSpecification Fields Constants Constructors Methods private