/*
* 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.cassandra.io.sstable.metadata;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.HashSet;
import java.util.Set;
import com.clearspring.analytics.stream.cardinality.HyperLogLogPlus;
import com.clearspring.analytics.stream.cardinality.ICardinality;
import org.apache.cassandra.db.TypeSizes;
import org.apache.cassandra.io.sstable.Descriptor;
import org.apache.cassandra.utils.ByteBufferUtil;
/**
* Compaction related SSTable metadata.
*
* Only loaded for <b>compacting</b> SSTables at the time of compaction.
*/
public class CompactionMetadata extends MetadataComponent
{
public static final IMetadataComponentSerializer serializer = new CompactionMetadataSerializer();
public final Set<Integer> ancestors;
public final ICardinality cardinalityEstimator;
public CompactionMetadata(Set<Integer> ancestors, ICardinality cardinalityEstimator)
{
this.ancestors = ancestors;
this.cardinalityEstimator = cardinalityEstimator;
}
public MetadataType getType()
{
return MetadataType.COMPACTION;
}
@Override
public boolean equals(Object o)
{
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
CompactionMetadata that = (CompactionMetadata) o;
return ancestors == null ? that.ancestors == null : ancestors.equals(that.ancestors);
}
@Override
public int hashCode()
{
return ancestors != null ? ancestors.hashCode() : 0;
}
public static class CompactionMetadataSerializer implements IMetadataComponentSerializer<CompactionMetadata>
{
public int serializedSize(CompactionMetadata component) throws IOException
{
int size = 0;
size += TypeSizes.NATIVE.sizeof(component.ancestors.size());
for (int g : component.ancestors)
size += TypeSizes.NATIVE.sizeof(g);
byte[] serializedCardinality = component.cardinalityEstimator.getBytes();
size += TypeSizes.NATIVE.sizeof(serializedCardinality.length) + serializedCardinality.length;
return size;
}
public void serialize(CompactionMetadata component, DataOutput out) throws IOException
{
out.writeInt(component.ancestors.size());
for (int g : component.ancestors)
out.writeInt(g);
ByteBufferUtil.writeWithLength(component.cardinalityEstimator.getBytes(), out);
}
public CompactionMetadata deserialize(Descriptor.Version version, DataInput in) throws IOException
{
int nbAncestors = in.readInt();
Set<Integer> ancestors = new HashSet<>(nbAncestors);
for (int i = 0; i < nbAncestors; i++)
ancestors.add(in.readInt());
ICardinality cardinality = HyperLogLogPlus.Builder.build(ByteBufferUtil.readBytes(in, in.readInt()));
return new CompactionMetadata(ancestors, cardinality);
}
}
}