com.illumon.iris.sbetransport.client

Class TableClient

java.lang.Object

com.illumon.iris.sbetransport.client.TableClient

All Implemented Interfaces:

AutoCloseable

public class TableClient
extends Object
implements AutoCloseable

A reference client for the Deephaven SBE table server.

This is intended as an illustration, not necessarily the most efficient way to implement a client.

Depending on the context, it may be desirable to implement an alternative to SimpleMessageHandler in a way that avoids memory allocation, decoding incoming SBE messages into existing buffers.

Constructor Summary

Constructors

Constructor and Description
TableClient(String host, int port, MessageHandler messageHandler) Start a new table client, connecting to the given host and port.
TableClient(String host, int port, MessageHandler messageHandler, boolean allocateDirect) Start a new table client, connecting to the given host and port.

Method Summary

Modifier and Type	Method and Description
void	close() Close the table client.
boolean	isAlive() Return if the client is still alive and processing incoming messages.
void	subscribe(int subscriptionId, SubscribeMode subscribeMode, String name) Subscribe to an exported table.
void	subscribe(int subscriptionId, SubscribeMode subscribeMode, String name, List<String> columnNames) Subscribe to an exported table.
void	subscribe(int subscriptionId, SubscribeMode subscribeMode, String name, List<String> columnNames, String filter) Subscribe to updates on the given columns for the table identified by the given name.
void	unsubscribe(int subscriptionId) Unsubscribe from updates for the given subscription id.

Methods inherited from class java.lang.Object

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

Constructor Detail

TableClient

public TableClient(String host,
                   int port,
                   MessageHandler messageHandler,
                   boolean allocateDirect)
            throws IOException

Start a new table client, connecting to the given host and port. Incoming messages will be sent to the given messageHandler object.

Parameters:

host - Host on which the TableServer is running

port - Port on which the TableServer is bound

messageHandler - Object which handles incoming messages from the server

allocateDirect - If true, use direct (off-heap) buffers to allocate message buffers

Throws:

IOException - If there is an error while connecting to the server

TableClient

public TableClient(String host,
                   int port,
                   MessageHandler messageHandler)
            throws IOException

Start a new table client, connecting to the given host and port. Incoming messages will be sent to the given messageHandler object. Message buffers will be allocated on the java heap (see TableClient.TableClient(String, int, MessageHandler, boolean)

Parameters:

host - Host on which the TableServer is running

port - Port on which the TableServer is bound

messageHandler - Object which handles incoming messages from the server

Throws:

IOException - If there is an error while connecting to the server

Method Detail

isAlive

public boolean isAlive()

Return if the client is still alive and processing incoming messages. Prior to death, the client should issue an handleConnectionError callback (unless death occurs through the TableClient.close() method.

Returns:

true if the client is still connected, false otherwise

close

public void close()
           throws InterruptedException,
                  IOException

Close the table client. This closes the socket connection and waits for the receive thread to die.

Specified by:

close in interface AutoCloseable

Throws:

InterruptedException - If interrupted while waiting for receive thread to die

IOException - If an error occurs while closing the socket

subscribe

public void subscribe(int subscriptionId,
                      SubscribeMode subscribeMode,
                      String name,
                      List<String> columnNames)
               throws IOException

Subscribe to an exported table. The given subscriptionId must be generated by the client and must be unique for this client. It will be used in all subsequent messages to identify updates for this subscription.

Parameters:

subscriptionId - A client generated unique identifier for this subscription

subscribeMode - Specifies whether the client is requesting an initial snapshot, update stream, or both

name - Exported table name (see exportTable on TableServer)

columnNames - List of columns for for which to receive updates (specify null for all columns)

Throws:

IOException - If an error occurs while sending to the server

subscribe

public void subscribe(int subscriptionId,
                      SubscribeMode subscribeMode,
                      String name)
               throws IOException

Subscribe to an exported table. The given subscriptionId must be generated by the client and must be unique for this client. It will be used in all subsequent messages to identify updates for this subscription.

Parameters:

subscriptionId - A client generated unique identifier for this subscription

subscribeMode - Specifies whether the client is requesting an initial snapshot, update stream, or both

name - Exported table name (see exportTable on TableServer)

Throws:

IOException - If an error occurs while sending to the server

subscribe

public void subscribe(int subscriptionId,
                      SubscribeMode subscribeMode,
                      String name,
                      List<String> columnNames,
                      String filter)
               throws IOException

Subscribe to updates on the given columns for the table identified by the given name. A client may subscribe to the same table any number of times, if unique subscription identifiers are provided for each subscription.

Parameters:

subscriptionId - A client generated unique identifier for this subscription

subscribeMode - Specifies whether the client is requesting an initial snapshot, update stream, or both

name - Exported table name (see exportTable on TableServer)

columnNames - List of columns for for which to receive updates (specify null for all columns)

filter - An expression to be used in a "where" clause to filter the desired table; in this way, only rows matching specified the criteria can be monitored (specify null for no filter)

Throws:

IOException - If an error occurs while sending to the server

unsubscribe

public void unsubscribe(int subscriptionId)
                 throws IOException

Unsubscribe from updates for the given subscription id.

Parameters:

subscriptionId - A subscription id previously used in a subscribe call

Throws:

IOException - If an error occurs while sending to the server