public function classExists($className)
    {
        if (!$className) {
            return false;
        }

        if (false === isset($this->existingClassList[$className])) {
            $this->existingClassList[$className] = class_exists($className) || interface_exists($className);
        }

        return $this->existingClassList[$className];
    }
public function classExists($className)
    {
        if (!$className) {
            return false;
        }

        if (false === isset($this->existingClassList[$className])) {
            $this->existingClassList[$className] = class_exists($className) || interface_exists($className);
        }

        return $this->existingClassList[$className];
    }
public function classExists ( $ className ) { if ( ! $ className ) { return false ; } if ( false === isset ( $ this -> existingClassList [ $ className ] ) ) { $ this -> existingClassList [ $ className ] = class_exists ( $ className ) || interface_exists ( $ className ) ; } return $ this -> existingClassList [ $ className ] ; }
Internal function which will check if the given class exists. This is
useful because of the calls to undefined class, which can lead to a lack
of performance due to the auto-loader called if the name of the class
is not registered yet.

This function will store the already checked class name in local cache.

@param string $className
@return bool
Internal function which will check if the given class exists . This is useful because of the calls to undefined class which can lead to a lack of performance due to the auto - loader called if the name of the class is not registered yet .