diff --git a/core/avatar/avatarcontroller.php b/core/avatar/avatarcontroller.php
index 5ddd80c45af7de44ea42ba1c7887ea7ef8e4c340..19ea1f7a4d8ba0e53155a08160b5ebb48e1d445e 100644
--- a/core/avatar/avatarcontroller.php
+++ b/core/avatar/avatarcontroller.php
@@ -43,7 +43,7 @@ class AvatarController extends Controller {
 	/** @var IAvatarManager */
 	protected $avatarManager;
 
-	/** @var ICache */
+	/** @var \OC\Cache\File */
 	protected $cache;
 
 	/** @var IL10N */
@@ -59,7 +59,7 @@ class AvatarController extends Controller {
 	 * @param string $appName
 	 * @param IRequest $request
 	 * @param IAvatarManager $avatarManager
-	 * @param ICache $cache
+	 * @param \OC\Cache\File $cache
 	 * @param IL10N $l10n
 	 * @param IUserManager $userManager
 	 * @param IUserSession $userSession
@@ -67,7 +67,7 @@ class AvatarController extends Controller {
 	public function __construct($appName,
 								IRequest $request,
 								IAvatarManager $avatarManager,
-								ICache $cache,
+								\OC\Cache\File $cache,
 								IL10N $l10n,
 								IUserManager $userManager,
 								IUserSession $userSession) {
diff --git a/lib/private/cache/file.php b/lib/private/cache/file.php
index bd3b5bc1cc1f6711d8a781b203a2e56ade4251a5..4742128ecbeec3c858722e4986e86b93a0846d32 100644
--- a/lib/private/cache/file.php
+++ b/lib/private/cache/file.php
@@ -42,6 +42,8 @@ class File {
 	 * Returns the cache storage for the logged in user
 	 *
 	 * @return \OC\Files\View cache storage
+	 * @throws \OC\ForbiddenException
+	 * @throws \OC\User\NoUserException
 	 */
 	protected function getStorage() {
 		if (isset($this->storage)) {
@@ -64,6 +66,8 @@ class File {
 
 	/**
 	 * @param string $key
+	 * @return mixed|null
+	 * @throws \OC\ForbiddenException
 	 */
 	public function get($key) {
 		$result = null;
@@ -91,6 +95,10 @@ class File {
 
 	/**
 	 * @param string $key
+	 * @param mixed $value
+	 * @param int $ttl
+	 * @return bool|mixed
+	 * @throws \OC\ForbiddenException
 	 */
 	public function set($key, $value, $ttl = 0) {
 		$storage = $this->getStorage();
@@ -114,6 +122,11 @@ class File {
 		return $result;
 	}
 
+	/**
+	 * @param string $key
+	 * @return bool
+	 * @throws \OC\ForbiddenException
+	 */
 	public function hasKey($key) {
 		$storage = $this->getStorage();
 		if ($storage && $storage->is_file($key) && $storage->isReadable($key)) {
@@ -124,6 +137,8 @@ class File {
 
 	/**
 	 * @param string $key
+	 * @return bool|mixed
+	 * @throws \OC\ForbiddenException
 	 */
 	public function remove($key) {
 		$storage = $this->getStorage();
@@ -133,6 +148,11 @@ class File {
 		return $storage->unlink($key);
 	}
 
+	/**
+	 * @param string $prefix
+	 * @return bool
+	 * @throws \OC\ForbiddenException
+	 */
 	public function clear($prefix = '') {
 		$storage = $this->getStorage();
 		if ($storage and $storage->is_dir('/')) {
@@ -148,6 +168,10 @@ class File {
 		return true;
 	}
 
+	/**
+	 * Runs GC
+	 * @throws \OC\ForbiddenException
+	 */
 	public function gc() {
 		$storage = $this->getStorage();
 		if ($storage and $storage->is_dir('/')) {
diff --git a/tests/core/avatar/avatarcontrollertest.php b/tests/core/avatar/avatarcontrollertest.php
index c58d7febc3f3227bf264adb3ca071031cd93dbf1..0a85fbb27f181ae81f2eef8b7108d12e246b2cea 100644
--- a/tests/core/avatar/avatarcontrollertest.php
+++ b/tests/core/avatar/avatarcontrollertest.php
@@ -62,7 +62,7 @@ class AvatarControllerTest extends \Test\TestCase {
 		$this->container['AppName'] = 'core';
 		$this->container['AvatarManager'] = $this->getMockBuilder('OCP\IAvatarManager')
 			->disableOriginalConstructor()->getMock();
-		$this->container['Cache'] = $this->getMockBuilder('OCP\ICache')
+		$this->container['Cache'] = $this->getMockBuilder('OC\Cache\File')
 			->disableOriginalConstructor()->getMock();
 		$this->container['L10N'] = $this->getMockBuilder('OCP\IL10N')
 			->disableOriginalConstructor()->getMock();