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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.ByteBufferUtil;
/**
* 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, and this mostly for thrift backward compatibility (in practice, if a value is null,
* all of the following ones will be too because that's what thrift allows, but it's never assumed by the
* code so we could start generally allowing nulls for clustering columns if we wanted to).
*/
public class BufferClustering extends AbstractBufferClusteringPrefix implements Clustering
{
BufferClustering(ByteBuffer... values)
{
super(Kind.CLUSTERING, values);
}
public ClusteringPrefix minimize()
{
if (!ByteBufferUtil.canMinimize(values))
return this;
return new BufferClustering(ByteBufferUtil.minimizeBuffers(values)); }
}