org.springframework.kafka.listener.adapter.FilteringBatchAcknowledgingMessageListenerAdapter Maven / Gradle / Ivy
/*
* Copyright 2016 the original author or 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 org.springframework.kafka.listener.adapter;
import java.util.Iterator;
import java.util.List;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.springframework.kafka.listener.BatchAcknowledgingMessageListener;
import org.springframework.kafka.support.Acknowledgment;
/**
* A {@link BatchAcknowledgingMessageListener} adapter that implements filter logic via a
* {@link RecordFilterStrategy}. Note that any discarded records will be ack'd when the
* delegate listener invokes {@code acknowledge()} on the {@link Acknowledgment}.
*
* @param the key type.
* @param the value type.
*
* @author Gary Russell
*
*/
public class FilteringBatchAcknowledgingMessageListenerAdapter
extends AbstractFilteringMessageListener>
implements BatchAcknowledgingMessageListener {
private final boolean ackDiscarded;
/**
* Create an instance with the supplied strategy and delegate listener; when all
* messages in a batch are discarded, an empty list is passed to the delegate so it
* can decide whether or not to acknowledge.
* @param delegate the delegate.
* @param recordFilterStrategy the filter.
*/
public FilteringBatchAcknowledgingMessageListenerAdapter(BatchAcknowledgingMessageListener delegate,
RecordFilterStrategy recordFilterStrategy) {
this(delegate, recordFilterStrategy, false);
}
/**
* Create an instance with the supplied strategy, delegate listener and discard
* action. When 'ackDiscarded' is false, and all messages are filtered, an empty list
* is passed to the delegate (so it can decided whether or not to ack); when true, a
* completely filtered batch is ack'd by this class, and no call is made to the delegate.
* @param delegate the delegate.
* @param recordFilterStrategy the filter.
* @param ackDiscarded true to ack automatically if all records are filtered.
*/
public FilteringBatchAcknowledgingMessageListenerAdapter(BatchAcknowledgingMessageListener delegate,
RecordFilterStrategy recordFilterStrategy, boolean ackDiscarded) {
super(delegate, recordFilterStrategy);
this.ackDiscarded = ackDiscarded;
}
@Override
public void onMessage(List> consumerRecords, Acknowledgment acknowledgment) {
Iterator> iterator = consumerRecords.iterator();
while (iterator.hasNext()) {
if (filter(iterator.next())) {
iterator.remove();
}
}
if (consumerRecords.size() > 0 || !this.ackDiscarded) {
this.delegate.onMessage(consumerRecords, acknowledgment);
}
else {
acknowledgment.acknowledge();
}
}
}