py4j

## Class JavaServer

- java.lang.Object
- - py4j.DefaultGatewayServerListener
  - - py4j.GatewayServer
    - - py4j.JavaServer

- All Implemented Interfaces:
    java.lang.Runnable, GatewayServerListener, Py4JJavaServer

      public class JavaServer
      extends GatewayServer

  This class extends GatewayServer by implementing a new threading model: a thread always use the same connection to the other side so callbacks are executed in the calling thread.

  For example, if Java thread 1 calls Python, and Python calls Java, the callback (from Python to Java) will be executed in Java thread 1.

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from class py4j.GatewayServer

      `GatewayServer.GatewayServerBuilder`

  - ### Field Summary

    - ### Fields inherited from class py4j.GatewayServer

      `DEFAULT_ADDRESS, DEFAULT_CONNECT_TIMEOUT, DEFAULT_IPv6_ADDRESS, DEFAULT_PORT, DEFAULT_PYTHON_PORT, DEFAULT_READ_TIMEOUT, GATEWAY_SERVER_ID, PY4J_LOGGER`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `JavaServer(java.lang.Object entryPoint, int port, int connectTimeout, int readTimeout, java.util.List<java.lang.Class<? extends Command>> customCommands, Py4JPythonClientPerThread pythonClient)`

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected Py4JServerConnection` | `createConnection(Gateway gateway, java.net.Socket socket)` Creates a server connection from a Python call to the Java side.

    - ### Methods inherited from class py4j.GatewayServer

      `addListener, connectionStopped, defaultAddress, defaultIPv6Address, fireConnectionError, fireConnectionStarted, fireServerError, fireServerPostShutdown, fireServerPreShutdown, fireServerStarted, fireServerStopped, getAddress, getCallbackClient, getConnectTimeout, getCustomCommands, getGateway, getListeners, getListeningPort, getPort, getPythonAddress, getPythonPort, getPythonServerEntryPoint, getReadTimeout, main, processSocket, removeListener, resetCallbackClient, run, shutdown, shutdown, start, start, startSocket, turnAllLoggingOn, turnLoggingOff, turnLoggingOn`

    - ### Methods inherited from class py4j.DefaultGatewayServerListener

      `connectionError, connectionStarted, serverError, serverPostShutdown, serverPreShutdown, serverStarted, serverStopped`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### JavaServer

          public JavaServer(java.lang.Object entryPoint,
                            int port,
                            int connectTimeout,
                            int readTimeout,
                            java.util.List<java.lang.Class<? extends Command>> customCommands,
                            Py4JPythonClientPerThread pythonClient)

      Parameters:
        `entryPoint` - The entry point of this Gateway. Can be null.
        `port` - The port the GatewayServer is listening to.
        `connectTimeout` - Time in milliseconds (0 = infinite). If a GatewayServer does not receive a connection request after this time, it closes the server socket and no other connection is accepted.
        `readTimeout` - Time in milliseconds (0 = infinite). Once a Python program is connected, if a GatewayServer does not receive a request (e.g., a method call) after this time, the connection with the Python program is closed.
        `customCommands` - A list of custom Command classes to augment the Server features. These commands will be accessible from Python programs. Can be null.
        `pythonClient` - The Py4JPythonClientPerThread used to call Python.

  - ### Method Detail

    - #### createConnection

          protected Py4JServerConnection createConnection(Gateway gateway,
                                                          java.net.Socket socket)
                                                   throws java.io.IOException

      Description copied from class: `GatewayServer`

      Creates a server connection from a Python call to the Java side.

      Overrides:
        `createConnection` in class `GatewayServer`
      Returns:
      Throws:
        `java.io.IOException`