org.apache.hudi.common.table.timeline.TimelineLayout 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.hudi.common.table.timeline;
import org.apache.hudi.common.table.timeline.versioning.TimelineLayoutVersion;
import org.apache.hudi.common.util.collection.Pair;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.Stream;
/**
* Timeline Layout responsible for applying specific filters when generating timeline instants.
*/
public abstract class TimelineLayout implements Serializable {
private static final Map LAYOUT_MAP = new HashMap<>();
static {
LAYOUT_MAP.put(new TimelineLayoutVersion(TimelineLayoutVersion.VERSION_0), new TimelineLayoutV0());
LAYOUT_MAP.put(new TimelineLayoutVersion(TimelineLayoutVersion.VERSION_1), new TimelineLayoutV1());
}
public static TimelineLayout getLayout(TimelineLayoutVersion version) {
return LAYOUT_MAP.get(version);
}
public abstract Stream filterHoodieInstants(Stream instantStream);
/**
* Table Layout where state transitions are managed by renaming files.
*/
private static class TimelineLayoutV0 extends TimelineLayout {
@Override
public Stream filterHoodieInstants(Stream instantStream) {
return instantStream;
}
}
/**
* Table Layout where state transitions are managed by creating new files.
*/
private static class TimelineLayoutV1 extends TimelineLayout {
@Override
public Stream filterHoodieInstants(Stream instantStream) {
return instantStream.collect(Collectors.groupingBy(instant -> Pair.of(instant.getTimestamp(),
HoodieInstant.getComparableAction(instant.getAction())))).values().stream()
.map(hoodieInstants -> hoodieInstants.stream().reduce((x, y) -> {
// Pick the one with the highest state
if (x.getState().compareTo(y.getState()) >= 0) {
return x;
}
return y;
}).get());
}
}
}