org.apache.kafka.streams.state.internals.MeteredWindowedKeyValueIterator Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.kafka.streams.state.internals;
import org.apache.kafka.common.metrics.Sensor;
import org.apache.kafka.common.utils.Bytes;
import org.apache.kafka.common.utils.Time;
import org.apache.kafka.streams.KeyValue;
import org.apache.kafka.streams.StreamsMetrics;
import org.apache.kafka.streams.kstream.Windowed;
import org.apache.kafka.streams.state.KeyValueIterator;
import java.util.function.Function;
class MeteredWindowedKeyValueIterator implements KeyValueIterator, V> {
private final KeyValueIterator, byte[]> iter;
private final Sensor sensor;
private final StreamsMetrics metrics;
private final Function deserializeKey;
private final Function deserializeValue;
private final long startNs;
private final Time time;
MeteredWindowedKeyValueIterator(final KeyValueIterator, byte[]> iter,
final Sensor sensor,
final StreamsMetrics metrics,
final Function deserializeKey,
final Function deserializeValue,
final Time time) {
this.iter = iter;
this.sensor = sensor;
this.metrics = metrics;
this.deserializeKey = deserializeKey;
this.deserializeValue = deserializeValue;
this.startNs = time.nanoseconds();
this.time = time;
}
@Override
public boolean hasNext() {
return iter.hasNext();
}
@Override
public KeyValue, V> next() {
final KeyValue, byte[]> next = iter.next();
return KeyValue.pair(windowedKey(next.key), deserializeValue.apply(next.value));
}
private Windowed windowedKey(final Windowed bytesKey) {
final K key = deserializeKey.apply(bytesKey.key().get());
return new Windowed<>(key, bytesKey.window());
}
@Override
public void close() {
try {
iter.close();
} finally {
sensor.record(time.nanoseconds() - startNs);
}
}
@Override
public Windowed peekNextKey() {
return windowedKey(iter.peekNextKey());
}
}