io.vertx.pgclient.pubsub

Interface PgChannel

All Superinterfaces:

ReadStream<String>, StreamBase

public interface PgChannel
extends ReadStream<String>

A channel to Postgres that tracks the subscription to a given Postgres channel using the LISTEN/UNLISTEN commands.

When paused the channel discards the messages.

Method Summary

Modifier and Type	Method and Description
PgChannel	endHandler(Handler<Void> endHandler) Set an handler to be called when no more notifications will be received.
PgChannel	exceptionHandler(Handler<Throwable> handler) Set an exception handler on the read stream.
PgChannel	handler(Handler<String> handler) Set or unset an handler to be called when a the channel is notified by Postgres.
PgChannel	pause() Pause the channel, all notifications are discarded.
PgChannel	resume() Resume the channel.
PgChannel	subscribeHandler(Handler<Void> handler) Set an handler called when the the channel get subscribed.

Methods inherited from interface io.vertx.core.streams.ReadStream

collect, fetch, pipe, pipeTo, pipeTo

Method Detail

subscribeHandler

PgChannel subscribeHandler(Handler<Void> handler)

Set an handler called when the the channel get subscribed.

Parameters:

handler - the handler

Returns:

a reference to this, so the API can be used fluently

handler

PgChannel handler(Handler<String> handler)

Set or unset an handler to be called when a the channel is notified by Postgres.

• when the handler is set, the subscriber sends a LISTEN command if needed
• when the handler is unset, the subscriber sends a UNLISTEN command if needed

Specified by:

handler in interface ReadStream<String>

Parameters:

handler - the handler

Returns:

a reference to this, so the API can be used fluently

pause

PgChannel pause()

Pause the channel, all notifications are discarded.

Specified by:

pause in interface ReadStream<String>

Returns:

a reference to this, so the API can be used fluently

resume

PgChannel resume()

Resume the channel.

Specified by:

resume in interface ReadStream<String>

Returns:

a reference to this, so the API can be used fluently

endHandler

PgChannel endHandler(Handler<Void> endHandler)

Set an handler to be called when no more notifications will be received.

Specified by:

endHandler in interface ReadStream<String>

Parameters:

endHandler - the handler

Returns:

a reference to this, so the API can be used fluently

exceptionHandler

PgChannel exceptionHandler(Handler<Throwable> handler)

Description copied from interface: ReadStream

Set an exception handler on the read stream.

Specified by:

exceptionHandler in interface ReadStream<String>

Specified by:

exceptionHandler in interface StreamBase

Parameters:

handler - the exception handler

Returns:

a reference to this, so the API can be used fluently