question: public static boolean available ( int port ) { if ( port < MIN_PORT_NUMBER || port > MAX_PORT_NUMBER ) { throw new IllegalArgumentException ( "Invalid start port: " + port ) ; } ServerSocket ss = null ; DatagramSocket ds = null ; try { ss = new ServerSocket ( port ) ; ss . setReuseAddress ( true ) ; ds = new DatagramSocket ( port ) ; ds . setReuseAddress ( true ) ; return true ; } catch ( IOException e ) { } finally { if ( ds != null ) { ds . close ( ) ; } if ( ss != null ) { try { ss . close ( ) ; } catch ( IOException e ) { } } } return false ; }
target:  Checks to see if a specific port is available.