py4j

Class GatewayConnection

java.lang.Object

py4j.GatewayConnection

All Implemented Interfaces:

Runnable, Py4JServerConnection

public class GatewayConnection
extends Object
implements Runnable, Py4JServerConnection

Manage the connection between a Python program and a Gateway. A GatewayConnection lives in its own thread and is created on demand (e.g., one per concurrent thread).

The request to connect to the JVM goes through the GatewayServer first and is then passed to a GatewayConnection.

This class is not intended to be directly accessed by users.

Author:

Barthelemy Dagenais

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<String,Command>	commands
protected List<GatewayServerListener>	listeners
protected Logger	logger
protected BufferedReader	reader
protected Socket	socket
protected BufferedWriter	writer

Constructor Summary

Constructors

Constructor and Description
GatewayConnection(Gateway gateway, Socket socket)
GatewayConnection(Gateway gateway, Socket socket, List<Class<? extends Command>> customCommands, List<GatewayServerListener> listeners)

Method Summary

Modifier and Type	Method and Description
protected void	fireConnectionStopped()
static List<Class<? extends Command>>	getBaseCommands()
Socket	getSocket()
protected void	initCommands(Gateway gateway, List<Class<? extends Command>> commandsClazz) Override this method to initialize custom commands.
protected void	quietSendFatalError(BufferedWriter writer, Throwable exception)
void	run()
void	shutdown()
void	shutdown(boolean reset) Shuts down the connection by closing the socket, the writer, and the reader.
void	startConnection() Wraps the GatewayConnection in a thread and start the thread.

Methods inherited from class java.lang.Object

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

Field Detail

socket

protected final Socket socket

writer

protected final BufferedWriter writer

reader

protected final BufferedReader reader

commands

protected final Map<String,Command> commands

logger

protected final Logger logger

listeners

protected final List<GatewayServerListener> listeners

Constructor Detail

GatewayConnection

public GatewayConnection(Gateway gateway,
                         Socket socket)
                  throws IOException

Throws:

IOException

GatewayConnection

public GatewayConnection(Gateway gateway,
                         Socket socket,
                         List<Class<? extends Command>> customCommands,
                         List<GatewayServerListener> listeners)
                  throws IOException

Throws:

IOException

Method Detail

getBaseCommands

public static List<Class<? extends Command>> getBaseCommands()

Returns:

The list of base commands that are provided by default. Can be hidden by custom commands with the same command id by passing a list of custom commands to the GatewayServer.

startConnection

public void startConnection()

Wraps the GatewayConnection in a thread and start the thread.

fireConnectionStopped

protected void fireConnectionStopped()

getSocket

public Socket getSocket()

Specified by:

getSocket in interface Py4JServerConnection

Returns:

The socket used by this gateway connection.

initCommands

protected void initCommands(Gateway gateway,
                            List<Class<? extends Command>> commandsClazz)

Override this method to initialize custom commands.

Parameters:

gateway -

quietSendFatalError

protected void quietSendFatalError(BufferedWriter writer,
                                   Throwable exception)

run

public void run()

Specified by:

run in interface Runnable

shutdown

public void shutdown()

Specified by:

shutdown in interface Py4JServerConnection

shutdown

public void shutdown(boolean reset)

Shuts down the connection by closing the socket, the writer, and the reader.

Internal: emits a connection stopped signal so GatewayServer can remove the connection from the connections list. In rare occasions, the shutdown method may be called twice (when the server shuts down at the same time as the connection fails and shuts down).

Specified by:

shutdown in interface Py4JServerConnection