org.apache.cassandra.db.BufferClustering Maven / Gradle / Ivy
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/*
* 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.db;
import java.nio.ByteBuffer;
import org.apache.cassandra.utils.ObjectSizes;
/**
* The clustering column values for a row.
*
* A {@code Clustering} is a {@code ClusteringPrefix} that must always be "complete", i.e. have
* as many values as there is clustering columns in the table it is part of. It is the clustering
* prefix used by rows.
*
* Note however that while it's size must be equal to the table clustering size, a clustering can have
* {@code null} values (this is currently only allowed in COMPACT table for historical reasons, but we
* could imagine lifting that limitation if we decide it make sense from a CQL point of view).
*/
public class BufferClustering extends AbstractBufferClusteringPrefix implements Clustering
{
private static final long EMPTY_SIZE = ObjectSizes.measure(new BufferClustering(EMPTY_VALUES_ARRAY));
public BufferClustering(ByteBuffer... values)
{
super(Kind.CLUSTERING, values);
}
public long unsharedHeapSize()
{
if (this == Clustering.EMPTY || this == Clustering.STATIC_CLUSTERING)
return 0;
return EMPTY_SIZE + ObjectSizes.sizeOnHeapOf(values);
}
public long unsharedHeapSizeExcludingData()
{
if (this == Clustering.EMPTY || this == Clustering.STATIC_CLUSTERING)
return 0;
return EMPTY_SIZE + ObjectSizes.sizeOnHeapExcludingDataOf(values);
}
public static BufferClustering make(ByteBuffer... values)
{
return new BufferClustering(values);
}
}