diff --git a/files/lib/data/message/Message.class.php b/files/lib/data/message/Message.class.php
index 9361fde..de0aa11 100644
--- a/files/lib/data/message/Message.class.php
+++ b/files/lib/data/message/Message.class.php
@@ -14,6 +14,10 @@
 
 namespace chat\data\message;
 
+use \chat\data\room\Room;
+use \wcf\data\object\type\ObjectType;
+use \wcf\data\object\type\ObjectTypeCache;
+
 /**
  * Represents a chat message.
  *
@@ -42,28 +46,22 @@ protected function handleData($data) {
 
 	/**
 	 * Returns whether this message already is inside the log.
-	 *
-	 * @return	boolean
 	 */
-	public function isInLog() {
+	public function isInLog(): bool {
 		return $this->time < (TIME_NOW - CHAT_ARCHIVE_AFTER);
 	}
 
 	/**
 	 * Returns the message type object of this message.
-	 *
-	 * @return	\wcf\data\object\type\ObjectType
 	 */
-	public function getMessageType() {
-		return \wcf\data\object\type\ObjectTypeCache::getInstance()->getObjectType($this->objectTypeID);
+	public function getMessageType(): ObjectType {
+		return ObjectTypeCache::getInstance()->getObjectType($this->objectTypeID);
 	}
 
 	/**
 	 * Returns the chat room that contains this message.
-	 *
-	 * @return	\chat\data\room\Room
 	 */
-	public function getRoom() {
+	public function getRoom(): Room {
 		return \chat\data\room\RoomCache::getInstance()->getRoom($this->roomID);
 	}
 }
diff --git a/files/lib/data/room/Room.class.php b/files/lib/data/room/Room.class.php
index 58a3601..de36be7 100644
--- a/files/lib/data/room/Room.class.php
+++ b/files/lib/data/room/Room.class.php
@@ -52,11 +52,8 @@ public function __toString() {
 	 * Returns whether the given user can see at least
 	 * one chat room. If no user is given the current user
 	 * should be assumed
-	 *
-	 * @param	\wcf\data\user\UserProfile	$user
-	 * @return	boolean
 	 */
-	public static function canSeeAny(\wcf\data\user\UserProfile $user = null) {
+	public static function canSeeAny(\wcf\data\user\UserProfile $user = null): bool {
 		$rooms = RoomCache::getInstance()->getRooms();
 		foreach ($rooms as $room) {
 			if ($room->canSee($user)) return true;
@@ -68,11 +65,8 @@ public static function canSeeAny(\wcf\data\user\UserProfile $user = null) {
 	/**
 	 * Returns whether the given user can see this room.
 	 * If no user is given the current user should be assumed.
-	 *
-	 * @param	\wcf\data\user\UserProfile	$user
-	 * @return	boolean
 	 */
-	public function canSee(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null) {
+	public function canSee(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null): bool {
 		static $cache = [ ];
 		if ($user === null) $user = new \wcf\data\user\UserProfile(WCF::getUser());
 
@@ -107,11 +101,8 @@ public function canSee(\wcf\data\user\UserProfile $user = null, \Exception &$rea
 	/**
 	 * Returns whether the given user can see the log of this room.
 	 * If no user is given the current user should be assumed.
-	 *
-	 * @param	\wcf\data\user\UserProfile	$user
-	 * @return	boolean
 	 */
-	public function canSeeLog(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null) {
+	public function canSeeLog(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null): bool {
 		static $cache = [ ];
 		if ($user === null) $user = new \wcf\data\user\UserProfile(WCF::getUser());
 
@@ -141,11 +132,8 @@ public function canSeeLog(\wcf\data\user\UserProfile $user = null, \Exception &$
 	/**
 	 * Returns whether the given user can join this room.
 	 * If no user is given the current user should be assumed.
-	 *
-	 * @param	\wcf\data\user\UserProfile	$user
-	 * @return	boolean
 	 */
-	public function canJoin(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null) {
+	public function canJoin(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null): bool {
 		static $cache = [ ];
 		if ($user === null) $user = new \wcf\data\user\UserProfile(WCF::getUser());
 
@@ -170,11 +158,8 @@ public function canJoin(\wcf\data\user\UserProfile $user = null, \Exception &$re
 	/**
 	 * Returns whether the given user can write public messages in this room.
 	 * If no user is given the current user should be assumed.
-	 *
-	 * @param	\wcf\data\user\UserProfile	$user
-	 * @return	boolean
 	 */
-	public function canWritePublicly(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null) {
+	public function canWritePublicly(\wcf\data\user\UserProfile $user = null, \Exception &$reason = null): bool {
 		static $cache = [ ];
 		if ($user === null) $user = new \wcf\data\user\UserProfile(WCF::getUser());