/*
* 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.filter;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.*;
import org.apache.cassandra.db.*;
import org.apache.cassandra.db.partitions.*;
import org.apache.cassandra.db.rows.*;
import org.apache.cassandra.db.transform.Transformation;
import org.apache.cassandra.io.sstable.format.SSTableReader;
import org.apache.cassandra.io.util.DataInputPlus;
import org.apache.cassandra.io.util.DataOutputPlus;
import org.apache.cassandra.schema.ColumnMetadata;
import org.apache.cassandra.schema.TableMetadata;
import org.apache.cassandra.utils.SearchIterator;
import org.apache.cassandra.utils.btree.BTreeSet;
/**
* A filter selecting rows given their clustering value.
*/
public class ClusteringIndexNamesFilter extends AbstractClusteringIndexFilter
{
static final InternalDeserializer deserializer = new NamesDeserializer();
// This could be empty if selectedColumns only has static columns (in which case the filter still
// selects the static row)
private final NavigableSet<Clustering> clusterings;
// clusterings is always in clustering order (because we need it that way in some methods), but we also
// sometimes need those clustering in "query" order (i.e. in reverse clustering order if the query is
// reversed), so we keep that too for simplicity.
private final NavigableSet<Clustering> clusteringsInQueryOrder;
public ClusteringIndexNamesFilter(NavigableSet<Clustering> clusterings, boolean reversed)
{
super(reversed);
assert !clusterings.contains(Clustering.STATIC_CLUSTERING);
this.clusterings = clusterings;
this.clusteringsInQueryOrder = reversed ? clusterings.descendingSet() : clusterings;
}
/**
* The set of requested rows.
*
* Please note that this can be empty if only the static row is requested.
*
* @return the set of requested clustering in clustering order (note that
* this is always in clustering order even if the query is reversed).
*/
public NavigableSet<Clustering> requestedRows()
{
return clusterings;
}
public boolean selectsAllPartition()
{
return false;
}
public boolean selects(Clustering clustering)
{
return clusterings.contains(clustering);
}
public ClusteringIndexNamesFilter forPaging(ClusteringComparator comparator, Clustering lastReturned, boolean inclusive)
{
NavigableSet<Clustering> newClusterings = reversed ?
clusterings.headSet(lastReturned, inclusive) :
clusterings.tailSet(lastReturned, inclusive);
return new ClusteringIndexNamesFilter(newClusterings, reversed);
}
public boolean isFullyCoveredBy(CachedPartition partition)
{
if (partition.isEmpty())
return false;
// 'partition' contains all columns, so it covers our filter if our last clusterings
// is smaller than the last in the cache
return clusterings.comparator().compare(clusterings.last(), partition.lastRow().clustering()) <= 0;
}
public boolean isHeadFilter()
{
return false;
}
// Given another iterator, only return the rows that match this filter
public UnfilteredRowIterator filterNotIndexed(ColumnFilter columnFilter, UnfilteredRowIterator iterator)
{
// Note that we don't filter markers because that's a bit trickier (we don't know in advance until when
// the range extend) and it's harmless to left them.
class FilterNotIndexed extends Transformation
{
@Override
public Row applyToStatic(Row row)
{
return columnFilter.fetchedColumns().statics.isEmpty() ? null : row.filter(columnFilter, iterator.metadata());
}
@Override
public Row applyToRow(Row row)
{
return clusterings.contains(row.clustering()) ? row.filter(columnFilter, iterator.metadata()) : null;
}
}
return Transformation.apply(iterator, new FilterNotIndexed());
}
public Slices getSlices(TableMetadata metadata)
{
Slices.Builder builder = new Slices.Builder(metadata.comparator, clusteringsInQueryOrder.size());
for (Clustering clustering : clusteringsInQueryOrder)
builder.add(Slice.make(clustering));
return builder.build();
}
public UnfilteredRowIterator getUnfilteredRowIterator(final ColumnFilter columnFilter, final Partition partition)
{
final Iterator<Clustering> clusteringIter = clusteringsInQueryOrder.iterator();
final SearchIterator<Clustering, Row> searcher = partition.searchIterator(columnFilter, reversed);
return new AbstractUnfilteredRowIterator(partition.metadata(),
partition.partitionKey(),
partition.partitionLevelDeletion(),
columnFilter.fetchedColumns(),
searcher.next(Clustering.STATIC_CLUSTERING),
reversed,
partition.stats())
{
protected Unfiltered computeNext()
{
while (clusteringIter.hasNext())
{
Row row = searcher.next(clusteringIter.next());
if (row != null)
return row;
}
return endOfData();
}
};
}
public boolean shouldInclude(SSTableReader sstable)
{
ClusteringComparator comparator = sstable.metadata().comparator;
List<ByteBuffer> minClusteringValues = sstable.getSSTableMetadata().minClusteringValues;
List<ByteBuffer> maxClusteringValues = sstable.getSSTableMetadata().maxClusteringValues;
// If any of the requested clustering is within the bounds covered by the sstable, we need to include the sstable
for (Clustering clustering : clusterings)
{
if (Slice.make(clustering).intersects(comparator, minClusteringValues, maxClusteringValues))
return true;
}
return false;
}
public String toString(TableMetadata metadata)
{
StringBuilder sb = new StringBuilder();
sb.append("names(");
int i = 0;
for (Clustering clustering : clusterings)
sb.append(i++ == 0 ? "" : ", ").append(clustering.toString(metadata));
if (reversed)
sb.append(", reversed");
return sb.append(')').toString();
}
public String toCQLString(TableMetadata metadata)
{
if (metadata.clusteringColumns().isEmpty() || clusterings.size() <= 1)
return "";
StringBuilder sb = new StringBuilder();
sb.append('(').append(ColumnMetadata.toCQLString(metadata.clusteringColumns())).append(')');
sb.append(clusterings.size() == 1 ? " = " : " IN (");
int i = 0;
for (Clustering clustering : clusterings)
sb.append(i++ == 0 ? "" : ", ").append("(").append(clustering.toCQLString(metadata)).append(")");
sb.append(clusterings.size() == 1 ? "" : ")");
appendOrderByToCQLString(metadata, sb);
return sb.toString();
}
public Kind kind()
{
return Kind.NAMES;
}
protected void serializeInternal(DataOutputPlus out, int version) throws IOException
{
ClusteringComparator comparator = (ClusteringComparator)clusterings.comparator();
out.writeUnsignedVInt(clusterings.size());
for (Clustering clustering : clusterings)
Clustering.serializer.serialize(clustering, out, version, comparator.subtypes());
}
protected long serializedSizeInternal(int version)
{
ClusteringComparator comparator = (ClusteringComparator)clusterings.comparator();
long size = TypeSizes.sizeofUnsignedVInt(clusterings.size());
for (Clustering clustering : clusterings)
size += Clustering.serializer.serializedSize(clustering, version, comparator.subtypes());
return size;
}
private static class NamesDeserializer implements InternalDeserializer
{
public ClusteringIndexFilter deserialize(DataInputPlus in, int version, TableMetadata metadata, boolean reversed) throws IOException
{
ClusteringComparator comparator = metadata.comparator;
BTreeSet.Builder<Clustering> clusterings = BTreeSet.builder(comparator);
int size = (int)in.readUnsignedVInt();
for (int i = 0; i < size; i++)
clusterings.add(Clustering.serializer.deserialize(in, version, comparator.subtypes()));
return new ClusteringIndexNamesFilter(clusterings.build(), reversed);
}
}
}