org.elasticsearch.common.network.CloseableChannel Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of elasticsearch Show documentation
Show all versions of elasticsearch Show documentation
Elasticsearch subproject :server
/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you 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 org.elasticsearch.common.network;
import org.elasticsearch.action.ActionFuture;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.support.PlainActionFuture;
import org.elasticsearch.core.internal.io.IOUtils;
import java.io.Closeable;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ExecutionException;
public interface CloseableChannel extends Closeable {
/**
* Closes the channel. For most implementations, this will be be an asynchronous process. For this
* reason, this method does not throw {@link java.io.IOException} There is no guarantee that the channel
* will be closed when this method returns. Use the {@link #addCloseListener(ActionListener)} method
* to implement logic that depends on knowing when the channel is closed.
*/
@Override
void close();
/**
* Adds a listener that will be executed when the channel is closed. If the channel is still open when
* this listener is added, the listener will be executed by the thread that eventually closes the
* channel. If the channel is already closed when the listener is added the listener will immediately be
* executed by the thread that is attempting to add the listener.
*
* @param listener to be executed
*/
void addCloseListener(ActionListener listener);
/**
* Indicates whether a channel is currently open
*
* @return boolean indicating if channel is open
*/
boolean isOpen();
/**
* Closes the channel without blocking.
*
* @param channel to close
*/
static void closeChannel(C channel) {
closeChannel(channel, false);
}
/**
* Closes the channel.
*
* @param channel to close
* @param blocking indicates if we should block on channel close
*/
static void closeChannel(C channel, boolean blocking) {
closeChannels(Collections.singletonList(channel), blocking);
}
/**
* Closes the channels.
*
* @param channels to close
* @param blocking indicates if we should block on channel close
*/
static void closeChannels(List channels, boolean blocking) {
try {
IOUtils.close(channels);
} catch (IOException e) {
// The CloseableChannel#close method does not throw IOException, so this should not occur.
throw new AssertionError(e);
}
if (blocking) {
ArrayList> futures = new ArrayList<>(channels.size());
for (final C channel : channels) {
PlainActionFuture closeFuture = PlainActionFuture.newFuture();
channel.addCloseListener(closeFuture);
futures.add(closeFuture);
}
blockOnFutures(futures);
}
}
static void blockOnFutures(List> futures) {
for (ActionFuture future : futures) {
try {
future.get();
} catch (ExecutionException e) {
// Ignore as we are only interested in waiting for the close process to complete. Logging
// close exceptions happens elsewhere.
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
}
}
}