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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright 2014 The Netty Project
*
* The Netty Project 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:
*
* https://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.netty.util.concurrent;
import io.netty.util.internal.PromiseNotificationUtil;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
import static io.netty.util.internal.ObjectUtil.checkNotNullWithIAE;
/**
* {@link GenericFutureListener} implementation which takes other {@link Promise}s
* and notifies them on completion.
*
* @param the type of value returned by the future
* @param the type of future
*/
public class PromiseNotifier> implements GenericFutureListener {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(PromiseNotifier.class);
private final Promise[] promises;
private final boolean logNotifyFailure;
/**
* Create a new instance.
*
* @param promises the {@link Promise}s to notify once this {@link GenericFutureListener} is notified.
*/
@SafeVarargs
public PromiseNotifier(Promise... promises) {
this(true, promises);
}
/**
* Create a new instance.
*
* @param logNotifyFailure {@code true} if logging should be done in case notification fails.
* @param promises the {@link Promise}s to notify once this {@link GenericFutureListener} is notified.
*/
@SafeVarargs
public PromiseNotifier(boolean logNotifyFailure, Promise... promises) {
checkNotNull(promises, "promises");
for (Promise promise: promises) {
checkNotNullWithIAE(promise, "promise");
}
this.promises = promises.clone();
this.logNotifyFailure = logNotifyFailure;
}
/**
* Link the {@link Future} and {@link Promise} such that if the {@link Future} completes the {@link Promise}
* will be notified. Cancellation is propagated both ways such that if the {@link Future} is cancelled
* the {@link Promise} is cancelled and vise-versa.
*
* @param future the {@link Future} which will be used to listen to for notifying the {@link Promise}.
* @param promise the {@link Promise} which will be notified
* @param the type of the value.
* @param the type of the {@link Future}
* @return the passed in {@link Future}
*/
public static > F cascade(final F future, final Promise promise) {
return cascade(true, future, promise);
}
/**
* Link the {@link Future} and {@link Promise} such that if the {@link Future} completes the {@link Promise}
* will be notified. Cancellation is propagated both ways such that if the {@link Future} is cancelled
* the {@link Promise} is cancelled and vise-versa.
*
* @param logNotifyFailure {@code true} if logging should be done in case notification fails.
* @param future the {@link Future} which will be used to listen to for notifying the {@link Promise}.
* @param promise the {@link Promise} which will be notified
* @param the type of the value.
* @param the type of the {@link Future}
* @return the passed in {@link Future}
*/
@SuppressWarnings({"unchecked", "rawtypes"})
public static > F cascade(boolean logNotifyFailure, final F future,
final Promise promise) {
promise.addListener(new FutureListener() {
@Override
public void operationComplete(Future f) {
if (f.isCancelled()) {
future.cancel(false);
}
}
});
future.addListener(new PromiseNotifier(logNotifyFailure, promise) {
@Override
public void operationComplete(Future f) throws Exception {
if (promise.isCancelled() && f.isCancelled()) {
// Just return if we propagate a cancel from the promise to the future and both are notified already
return;
}
super.operationComplete(future);
}
});
return future;
}
@Override
public void operationComplete(F future) throws Exception {
InternalLogger internalLogger = logNotifyFailure ? logger : null;
if (future.isSuccess()) {
V result = future.get();
for (Promise p: promises) {
PromiseNotificationUtil.trySuccess(p, result, internalLogger);
}
} else if (future.isCancelled()) {
for (Promise p: promises) {
PromiseNotificationUtil.tryCancel(p, internalLogger);
}
} else {
Throwable cause = future.cause();
for (Promise p: promises) {
PromiseNotificationUtil.tryFailure(p, cause, internalLogger);
}
}
}
}