php – Zend Framework – 在oop原理中,方法’$this-> getReq

/**
     * Instantiate default request object (HTTP version) if none provided
     */
    if (null !== $request) {
        $this->setRequest($request);
    } elseif ((null === $request) && (null === ($request = $this->getRequest()))) {
        require_once 'Zend/Controller/Request/Http.php';
        $request = new Zend_Controller_Request_Http();
        $this->setRequest($request);
    }

The purpose of frontcontroller is to initialize the request
environment,route the incoming request,and then dispatch any
discovered actions; it aggregates any responses and returns them when
the process is complete.

有关FrontController here的更多信息

进一步回答您的问题

/**
 * Return the Request object
 *
 * @return Zend_Controller_Request_Abstract
 */
public function getRequest()
{
    return $this->_request;
}

这就是Zend / Controller / Action.php中的内容 – 这里的评论说Zend_Controller_Request_Abstract’是’a’返回类型.我突出显示’is-a’,因为它可以返回任何’是-a’Zend_Controller_Request_Abstract的类.更多关于是 – 检查这个wikipedia页面

“In knowledge representation,object-oriented programming and design,is-a or is_a or is a (subsumption) is a relationship where one class D is a subclass of another class B (and so B is a superclass of D).”