check whether the message with this id has been already received . concode_field_sep String MESSAGE_ID_HEADER concode_elem_sep String MESSAGE_TYPE_IMAGE concode_elem_sep int MESSAGE_ID_HISTORY_LENGTH concode_elem_sep byte[] imageBuffer concode_elem_sep String MESSAGE_TYPE_TEXT concode_elem_sep byte historyIndex concode_elem_sep byte[] buffer concode_elem_sep String[] messageIdHistory concode_field_sep void process
boolean function ( String arg0 ) { if ( arg0 == null ) { return false ; } if ( Arrays . contains ( messageIdHistory , arg0 ) ) { return true ; } messageIdHistory [ historyIndex ++ ] = arg0 ; if ( historyIndex >= MESSAGE_ID_HISTORY_LENGTH ) { historyIndex = 0 ; } return false ; }