/*
 * Copyright (C) 2017 Julien Viet
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package io.vertx.pgclient.pubsub;

import io.vertx.codegen.annotations.Fluent;
import io.vertx.codegen.annotations.VertxGen;
import io.vertx.core.Handler;
import io.vertx.core.streams.ReadStream;

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.
/** * A channel to Postgres that tracks the subscription to a given Postgres channel using the {@code LISTEN/UNLISTEN} commands. * <p/> * When paused the channel discards the messages. */
@VertxGen public interface PgChannel extends ReadStream<String> {
Set an handler called when the the channel get subscribed.
Params:
  • handler – the handler
Returns:a reference to this, so the API can be used fluently
/** * Set an handler called when the the channel get subscribed. * * @param handler the handler * @return a reference to this, so the API can be used fluently */
@Fluent PgChannel subscribeHandler(Handler<Void> 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
Params:
  • handler – the handler
Returns:a reference to this, so the API can be used fluently
/** * Set or unset an handler to be called when a the channel is notified by Postgres. * <p/> * <ul> * <li>when the handler is set, the subscriber sends a {@code LISTEN} command if needed</li> * <li>when the handler is unset, the subscriber sends a {@code UNLISTEN} command if needed</li> * </ul> * * @param handler the handler * @return a reference to this, so the API can be used fluently */
@Override PgChannel handler(Handler<String> handler);
Pause the channel, all notifications are discarded.
Returns:a reference to this, so the API can be used fluently
/** * Pause the channel, all notifications are discarded. * * @return a reference to this, so the API can be used fluently */
@Override PgChannel pause();
Resume the channel.
Returns:a reference to this, so the API can be used fluently
/** * Resume the channel. * * @return a reference to this, so the API can be used fluently */
@Override PgChannel resume();
Set an handler to be called when no more notifications will be received.
Params:
  • endHandler – the handler
Returns:a reference to this, so the API can be used fluently
/** * Set an handler to be called when no more notifications will be received. * * @param endHandler the handler * @return a reference to this, so the API can be used fluently */
@Override PgChannel endHandler(Handler<Void> endHandler); @Override PgChannel exceptionHandler(Handler<Throwable> handler); }