io.grpc.internal.SquelchLateMessagesAvailableDeframerListener Maven / Gradle / Ivy
/*
* Copyright 2020 The gRPC Authors
*
* 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.grpc.internal;
import java.io.Closeable;
/**
* A delegating Listener that throws away notifications of messagesAvailable() after the deframer
* has closed or failed. This can be used by deframers that "abuse" the MessageProducer to run work
* on the app thread, to avoid breaking the normal invariant that there are no messages after
* deframing is complete. Since the producer may not be run, it must not hold resources or
* it should implement {@link Closeable}.
*/
final class SquelchLateMessagesAvailableDeframerListener extends ForwardingDeframerListener {
private final MessageDeframer.Listener delegate;
private boolean closed;
public SquelchLateMessagesAvailableDeframerListener(MessageDeframer.Listener delegate) {
this.delegate = delegate;
}
@Override
protected MessageDeframer.Listener delegate() {
return delegate;
}
@Override
public void messagesAvailable(StreamListener.MessageProducer producer) {
if (closed) {
if (producer instanceof Closeable) {
GrpcUtil.closeQuietly((Closeable) producer);
}
return;
}
super.messagesAvailable(producer);
}
@Override
public void deframerClosed(boolean hasPartialMessage) {
closed = true;
super.deframerClosed(hasPartialMessage);
}
@Override
public void deframeFailed(Throwable cause) {
closed = true;
super.deframeFailed(cause);
}
}