public static void main()

in paimon-python-java-bridge/src/main/java/org/apache/paimon/python/PythonGatewayServer.java [44:102]
52 lines of code
7 McCabe index (conditional complexity)

    public static void main(String[] args)
            throws IOException, ExecutionException, InterruptedException, ClassNotFoundException {
        GatewayServer gatewayServer = PythonEnvUtils.startGatewayServer();
        PythonEnvUtils.setGatewayServer(gatewayServer);

        int boundPort = gatewayServer.getListeningPort();
        Py4JPythonClient callbackClient = gatewayServer.getCallbackClient();
        int callbackPort = callbackClient.getPort();
        if (boundPort == -1) {
            System.out.println("GatewayServer failed to bind; exiting");
            System.exit(1);
        }

        // Tells python side the port of our java rpc server
        String handshakeFilePath = System.getenv("_PYPAIMON_CONN_INFO_PATH");
        File handshakeFile = new File(handshakeFilePath);
        File tmpPath =
                Files.createTempFile(handshakeFile.getParentFile().toPath(), "connection", ".info")
                        .toFile();
        FileOutputStream fileOutputStream = new FileOutputStream(tmpPath);
        DataOutputStream stream = new DataOutputStream(fileOutputStream);
        stream.writeInt(boundPort);
        stream.writeInt(callbackPort);
        stream.close();
        fileOutputStream.close();

        if (!tmpPath.renameTo(handshakeFile)) {
            System.out.println(
                    "Unable to write connection information to handshake file: "
                            + handshakeFilePath
                            + ", now exit...");
            System.exit(1);
        }

        try {
            // This ensures that the server dies if its parent program dies.
            Map<String, Object> entryPoint =
                    (Map<String, Object>) gatewayServer.getGateway().getEntryPoint();

            for (int i = 0; i < TIMEOUT_MILLIS / CHECK_INTERVAL; i++) {
                if (entryPoint.containsKey("Watchdog")) {
                    break;
                }
                Thread.sleep(CHECK_INTERVAL);
            }
            if (!entryPoint.containsKey("Watchdog")) {
                System.out.println("Unable to get the Python watchdog object, now exit.");
                System.exit(1);
            }
            Watchdog watchdog = (Watchdog) entryPoint.get("Watchdog");
            while (watchdog.ping()) {
                Thread.sleep(CHECK_INTERVAL);
            }
            gatewayServer.shutdown();
            System.exit(0);
        } finally {
            System.exit(1);
        }
    }