question: public RejoinGroupChatSession rejoinGroupChatSession ( String chatId ) { boolean logActivated = sLogger . isActivated ( ) ; if ( logActivated ) { sLogger . info ( "Rejoin group chat session" ) ; } assertAvailableChatSession ( "Max chat sessions reached" ) ; GroupChatInfo groupChat = mMessagingLog . getGroupChatInfo ( chatId ) ; if ( groupChat == null ) { if ( logActivated ) { sLogger . warn ( "Group chat " + chatId + " can't be rejoined: conversation not found" ) ; } throw new ServerApiPersistentStorageException ( "Group chat conversation not found in database" ) ; } if ( groupChat . getRejoinId ( ) == null ) { if ( logActivated ) { sLogger . warn ( "Group chat " + chatId + " can't be rejoined: rejoin ID not found" ) ; } throw new ServerApiPersistentStorageException ( "Rejoin ID not found in database" ) ; } if ( logActivated ) { sLogger . debug ( "Rejoin group chat: " + groupChat . toString ( ) ) ; } long timestamp = groupChat . getTimestamp ( ) ; return new RejoinGroupChatSession ( this , groupChat , mRcsSettings , mMessagingLog , timestamp , mContactManager ) ; }
target:  Rejoin a group chat session