question: private IgniteBiTuple < String , Integer > hostPort ( String connStr , String hostPortStr ) throws IgniteCheckedException { String [ ] tokens = hostPortStr . split ( ":" , - 1 ) ; String host = tokens [ 0 ] ; if ( F . isEmpty ( host ) ) host = LOCALHOST ; int port ; if ( tokens . length == 1 ) port = IgfsIpcEndpointConfiguration . DFLT_PORT ; else if ( tokens . length == 2 ) { String portStr = tokens [ 1 ] ; try { port = Integer . valueOf ( portStr ) ; if ( port < 0 || port > 65535 ) throw new IgniteCheckedException ( "Invalid port number: " + connStr ) ; } catch ( NumberFormatException e ) { throw new IgniteCheckedException ( "Invalid port number: " + connStr ) ; } } else throw new IgniteCheckedException ( "Invalid connection string format: " + connStr ) ; return F . t ( host , port ) ; }
target:  Parse host and port.