com.taosdata.jdbc.ws

Class WSConnectionManager

java.lang.Object

com.taosdata.jdbc.ws.WSConnectionManager

All Implemented Interfaces:

AutoCloseable

public class WSConnectionManager
extends Object
implements AutoCloseable

Manages WebSocket connections, reconnection, and load balancing for TDengine. Handles connection lifecycle including initial connection, reconnection on failure, and balancing connections across multiple endpoints.

Constructor Summary

Constructors

Constructor and Description
WSConnectionManager(WSFunction function, ConnectionParam param, InFlightRequest inFlightRequest) Constructs a new WSConnectionManager with the specified parameters.

Method Summary

Modifier and Type	Method and Description
boolean	authenticateAfterReconnect(Transport transport) Performs authentication after physical reconnection.
void	balanceConnection(Transport transport) Balances connections across available endpoints by switching to the least loaded endpoint.
void	checkConnection(int connectTimeout) Checks and establishes connection to TDengine servers.
void	close() Closes all connections and releases resources.
ConnectionParam	getConnectionParam() Gets the connection parameters.
WSClient	getCurrentClient() Gets the current active WebSocket client.
Endpoint	getCurrentEndpoint() Gets the current active endpoint.
int	getReconnectCount() Gets the number of reconnection attempts made.
boolean	isClosed() Checks if this connection manager is closed.
boolean	isConnected() Checks if the current connection is open and active.
boolean	isConnectionLost() Checks if the current connection is closed or lost.
void	performReconnect(boolean isTmq, Transport transport) Performs complete reconnection process including physical reconnection and authentication.
void	tmqRethrowConnectionCloseException() Throws special connection closed exception for TMQ connections.

Methods inherited from class java.lang.Object

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

Constructor Detail

WSConnectionManager

public WSConnectionManager(WSFunction function,
                           ConnectionParam param,
                           InFlightRequest inFlightRequest)
                    throws SQLException

Constructs a new WSConnectionManager with the specified parameters.

Parameters:

function - the WebSocket function type

param - the connection parameters

inFlightRequest - the in-flight request manager

Throws:

SQLException - if connection initialization fails

Method Detail

performReconnect

public void performReconnect(boolean isTmq,
                             Transport transport)
                      throws SQLException

Performs complete reconnection process including physical reconnection and authentication.

Parameters:

isTmq - whether this is a TMQ connection (TMQ has different reconnection behavior)

transport - the transport instance for sending authentication requests

Throws:

SQLException - if reconnection fails for all endpoints

authenticateAfterReconnect

public boolean authenticateAfterReconnect(Transport transport)
                                   throws SQLException

Performs authentication after physical reconnection.

Parameters:

transport - the transport instance for sending authentication request

Returns:

true if authentication successful, false otherwise

Throws:

SQLException - if authentication request fails

checkConnection

public void checkConnection(int connectTimeout)
                     throws SQLException

Checks and establishes connection to TDengine servers. For first connection with slave cluster, tests all nodes and keeps only the current connection. For subsequent connections, uses load balancing to select the best endpoint.

Parameters:

connectTimeout - the connection timeout in milliseconds

Throws:

SQLException - if connection cannot be established within timeout

balanceConnection

public void balanceConnection(Transport transport)

Balances connections across available endpoints by switching to the least loaded endpoint.

Parameters:

transport - the transport instance for sending authentication during switch

getCurrentClient

public WSClient getCurrentClient()

Gets the current active WebSocket client.

Returns:

the current WSClient instance

isConnected

public boolean isConnected()

Checks if the current connection is open and active.

Returns:

true if connected, false otherwise

isConnectionLost

public boolean isConnectionLost()

Checks if the current connection is closed or lost.

Returns:

true if connection is lost, false otherwise

getReconnectCount

public int getReconnectCount()

Gets the number of reconnection attempts made.

Returns:

the reconnection count

getConnectionParam

public ConnectionParam getConnectionParam()

Gets the connection parameters.

Returns:

the connection parameters

getCurrentEndpoint

public Endpoint getCurrentEndpoint()

Gets the current active endpoint.

Returns:

the current endpoint

isClosed

public boolean isClosed()

Checks if this connection manager is closed.

Returns:

true if closed, false otherwise

close

public void close()

Closes all connections and releases resources.

Specified by:

close in interface AutoCloseable

tmqRethrowConnectionCloseException

public void tmqRethrowConnectionCloseException()
                                        throws SQLException

Throws special connection closed exception for TMQ connections. TMQ handles reconnection differently in its poll mechanism.

Throws:

SQLException - always throws TMQ-specific connection closed exception