org.asynchttpclient.shaded.netty.channel.PerHostConnectionSemaphore Maven / Gradle / Ivy
/*
* Copyright (c) 2018 AsyncHttpClient Project. All rights reserved.
*
* This program is licensed to you under the Apache License Version 2.0,
* and you may not use this file except in compliance with the Apache License Version 2.0.
* You may obtain a copy of the Apache License Version 2.0 at
* http://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the Apache License Version 2.0 is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the Apache License Version 2.0 for the specific language governing permissions and limitations there under.
*/
package org.asynchttpclient.shaded.netty.channel;
import org.asynchttpclient.shaded.exception.TooManyConnectionsPerHostException;
import java.io.IOException;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
import static org.asynchttpclient.shaded.util.ThrowableUtil.unknownStackTrace;
/**
* Max per-host connections limiter.
*/
public class PerHostConnectionSemaphore implements ConnectionSemaphore {
protected final ConcurrentHashMap freeChannelsPerHost = new ConcurrentHashMap<>();
protected final int maxConnectionsPerHost;
protected final IOException tooManyConnectionsPerHost;
protected final int acquireTimeout;
PerHostConnectionSemaphore(int maxConnectionsPerHost, int acquireTimeout) {
tooManyConnectionsPerHost = unknownStackTrace(new TooManyConnectionsPerHostException(maxConnectionsPerHost), PerHostConnectionSemaphore.class, "acquireChannelLock");
this.maxConnectionsPerHost = maxConnectionsPerHost;
this.acquireTimeout = Math.max(0, acquireTimeout);
}
@Override
public void acquireChannelLock(Object partitionKey) throws IOException {
try {
if (!getFreeConnectionsForHost(partitionKey).tryAcquire(acquireTimeout, TimeUnit.MILLISECONDS)) {
throw tooManyConnectionsPerHost;
}
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
@Override
public void releaseChannelLock(Object partitionKey) {
getFreeConnectionsForHost(partitionKey).release();
}
protected Semaphore getFreeConnectionsForHost(Object partitionKey) {
return maxConnectionsPerHost > 0 ?
freeChannelsPerHost.computeIfAbsent(partitionKey, pk -> new Semaphore(maxConnectionsPerHost)) :
InfiniteSemaphore.INSTANCE;
}
}