magento2/app/code/Magento/Backend/Controller/Adminhtml/Cache.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

namespace Magento\Backend\Controller\Adminhtml;

use Magento\Backend\App\Action;
use Magento\Framework\Exception\LocalizedException;

abstract class Cache extends Action
{
    /**
     * Authorization level of a basic admin session
     *
     * @see _isAllowed()
     */
    const ADMIN_RESOURCE = 'Magento_Backend::cache';

    /**
     * @var \Magento\Framework\App\Cache\TypeListInterface
     */
    protected $_cacheTypeList;

    /**
     * @var \Magento\Framework\App\Cache\StateInterface
     */
    protected $_cacheState;

    /**
     * @var \Magento\Framework\App\Cache\Frontend\Pool
     */
    protected $_cacheFrontendPool;

    /**
     * @var \Magento\Framework\View\Result\PageFactory
     */
    protected $resultPageFactory;

    /**
     * @param Action\Context $context
     * @param \Magento\Framework\App\Cache\TypeListInterface $cacheTypeList
     * @param \Magento\Framework\App\Cache\StateInterface $cacheState
     * @param \Magento\Framework\App\Cache\Frontend\Pool $cacheFrontendPool
     * @param \Magento\Framework\View\Result\PageFactory $resultPageFactory
     */
    public function __construct(
        Action\Context $context,
        \Magento\Framework\App\Cache\TypeListInterface $cacheTypeList,
        \Magento\Framework\App\Cache\StateInterface $cacheState,
        \Magento\Framework\App\Cache\Frontend\Pool $cacheFrontendPool,
        \Magento\Framework\View\Result\PageFactory $resultPageFactory
    ) {
        parent::__construct($context);
        $this->_cacheTypeList = $cacheTypeList;
        $this->_cacheState = $cacheState;
        $this->_cacheFrontendPool = $cacheFrontendPool;
        $this->resultPageFactory = $resultPageFactory;
    }

    /**
     * Check whether specified cache types exist
     *
     * @param array $types
     * @return void
     * @throws \Magento\Framework\Exception\LocalizedException
     */
    protected function _validateTypes(array $types)
    {
        if (empty($types)) {
            return;
        }
        $allTypes = array_keys($this->_cacheTypeList->getTypes());
        $invalidTypes = array_diff($types, $allTypes);
        if (count($invalidTypes) > 0) {
            throw new LocalizedException(__('These cache type(s) don\'t exist: %1', join(', ', $invalidTypes)));
        }
    }
}