| /* |
| * 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 com.google.common.annotations.VisibleForTesting; |
| |
| import org.apache.cassandra.utils.ByteBufferUtil; |
| |
| /** |
| * The clustering column values for a row. |
| * <p> |
| * 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. |
| * <p> |
| * 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 |
| { |
| @VisibleForTesting |
| public BufferClustering(ByteBuffer... values) |
| { |
| super(Kind.CLUSTERING, values); |
| } |
| |
| public ClusteringPrefix minimize() |
| { |
| if (!ByteBufferUtil.canMinimize(values)) |
| return this; |
| return new BufferClustering(ByteBufferUtil.minimizeBuffers(values)); } |
| } |