Contao\ContentAlias::generate PHP Method

    public function generate()
    {
        $objElement = \ContentModel::findByPk($this->cteAlias);
        if ($objElement === null) {
            return '';
        }
        $strClass = static::findClass($objElement->type);
        if (!class_exists($strClass)) {
            return '';
        }
        $objElement->origId = $objElement->id;
        $objElement->id = $this->id;
        $objElement->typePrefix = 'ce_';
        /** @var ContentElement $objElement */
        $objElement = new $strClass($objElement);
        $cssID = \StringUtil::deserialize($objElement->cssID, true);
        // Override the CSS ID (see #305)
        if (!empty($this->cssID[0])) {
            $cssID[0] = $this->cssID[0];
        }
        // Merge the CSS classes (see #6011)
        if (!empty($this->cssID[1])) {
            $cssID[1] = trim($cssID[1] . ' ' . $this->cssID[1]);
        }
        $objElement->cssID = $cssID;
        return $objElement->generate();
    }