| /* |
| * 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.aggregation; |
| |
| import java.io.IOException; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import org.apache.cassandra.cql3.QueryOptions; |
| import org.apache.cassandra.cql3.functions.Function; |
| import org.apache.cassandra.cql3.selection.Selector; |
| import org.apache.cassandra.db.ClusteringComparator; |
| import org.apache.cassandra.db.TypeSizes; |
| 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; |
| |
| /** |
| * Defines how rows should be grouped for creating aggregates. |
| */ |
| public abstract class AggregationSpecification |
| { |
| public static final Serializer serializer = new Serializer(); |
| |
| /** |
| * <code>AggregationSpecification</code> that group all the row together. |
| */ |
| public static final AggregationSpecification AGGREGATE_EVERYTHING = new AggregationSpecification(Kind.AGGREGATE_EVERYTHING) |
| { |
| @Override |
| public GroupMaker newGroupMaker(GroupingState state) |
| { |
| return GroupMaker.GROUP_EVERYTHING; |
| } |
| }; |
| |
| /** |
| * Factory for <code>AggregationSpecification</code> that group all the row together. |
| */ |
| public static final AggregationSpecification.Factory AGGREGATE_EVERYTHING_FACTORY = options -> AGGREGATE_EVERYTHING; |
| |
| /** |
| * The <code>AggregationSpecification</code> kind. |
| */ |
| private final Kind kind; |
| |
| /** |
| * The <code>AggregationSpecification</code> kinds. |
| */ |
| public enum Kind |
| { |
| AGGREGATE_EVERYTHING, AGGREGATE_BY_PK_PREFIX, AGGREGATE_BY_PK_PREFIX_WITH_SELECTOR |
| } |
| |
| /** |
| * Returns the <code>AggregationSpecification</code> kind. |
| * @return the <code>AggregationSpecification</code> kind |
| */ |
| public Kind kind() |
| { |
| return kind; |
| } |
| |
| private AggregationSpecification(Kind kind) |
| { |
| this.kind = kind; |
| } |
| |
| /** |
| * Creates a new <code>GroupMaker</code> instance. |
| * |
| * @return a new <code>GroupMaker</code> instance |
| */ |
| public final GroupMaker newGroupMaker() |
| { |
| return newGroupMaker(GroupingState.EMPTY_STATE); |
| } |
| |
| /** |
| * Creates a new <code>GroupMaker</code> instance. |
| * |
| * @param state <code>GroupMaker</code> state |
| * @return a new <code>GroupMaker</code> instance |
| */ |
| public abstract GroupMaker newGroupMaker(GroupingState state); |
| |
| /** |
| * Creates a new {@code Factory} instance to create {@code AggregationSpecification} that will build aggregates |
| * based on primary key columns. |
| * |
| * @param comparator the comparator used to compare the clustering prefixes |
| * @param clusteringPrefixSize the number of clustering columns used to create the aggregates |
| * @return a new {@code Factory} instance to create {@code AggregationSpecification} that will build aggregates |
| * based on primary key columns. |
| */ |
| public static AggregationSpecification.Factory aggregatePkPrefixFactory(ClusteringComparator comparator, |
| int clusteringPrefixSize) |
| { |
| return options -> new AggregateByPkPrefix(comparator, clusteringPrefixSize); |
| } |
| |
| public static AggregationSpecification.Factory aggregatePkPrefixFactoryWithSelector(final ClusteringComparator comparator, |
| final int clusteringPrefixSize, |
| final Selector.Factory factory, |
| final List<ColumnMetadata> columns) |
| { |
| return new Factory() |
| { |
| @Override |
| public void addFunctionsTo(List<Function> functions) |
| { |
| factory.addFunctionsTo(functions); |
| } |
| |
| @Override |
| public AggregationSpecification newInstance(QueryOptions options) |
| { |
| Selector selector = factory.newInstance(options); |
| selector.validateForGroupBy(); |
| return new AggregateByPkPrefixWithSelector(comparator, |
| clusteringPrefixSize, |
| selector, |
| columns); |
| } |
| }; |
| } |
| |
| /** |
| * Factory for {@code AggregationSpecification}. |
| * |
| */ |
| public static interface Factory |
| { |
| /** |
| * Creates a new {@code AggregationSpecification} instance after having binded the parameters. |
| * |
| * @param options the query options |
| * @return a new {@code AggregationSpecification} instance. |
| */ |
| public AggregationSpecification newInstance(QueryOptions options); |
| |
| public default void addFunctionsTo(List<Function> functions) |
| { |
| } |
| } |
| |
| /** |
| * <code>AggregationSpecification</code> that build aggregates based on primary key columns |
| */ |
| private static class AggregateByPkPrefix extends AggregationSpecification |
| { |
| /** |
| * The number of clustering component to compare. |
| */ |
| protected final int clusteringPrefixSize; |
| |
| /** |
| * The comparator used to compare the clustering prefixes. |
| */ |
| protected final ClusteringComparator comparator; |
| |
| public AggregateByPkPrefix(ClusteringComparator comparator, int clusteringPrefixSize) |
| { |
| this(Kind.AGGREGATE_BY_PK_PREFIX, comparator, clusteringPrefixSize); |
| } |
| |
| protected AggregateByPkPrefix(Kind kind, ClusteringComparator comparator, int clusteringPrefixSize) |
| { |
| super(kind); |
| this.comparator = comparator; |
| this.clusteringPrefixSize = clusteringPrefixSize; |
| } |
| |
| @Override |
| public GroupMaker newGroupMaker(GroupingState state) |
| { |
| return GroupMaker.newPkPrefixGroupMaker(comparator, clusteringPrefixSize, state); |
| } |
| } |
| |
| /** |
| * <code>AggregationSpecification</code> that build aggregates based on primary key columns using a selector. |
| */ |
| private static final class AggregateByPkPrefixWithSelector extends AggregateByPkPrefix |
| { |
| /** |
| * The selector. |
| */ |
| private final Selector selector; |
| |
| /** |
| * The columns used by the selector. |
| */ |
| private final List<ColumnMetadata> columns; |
| |
| public AggregateByPkPrefixWithSelector(ClusteringComparator comparator, |
| int clusteringPrefixSize, |
| Selector selector, |
| List<ColumnMetadata> columns) |
| { |
| super(Kind.AGGREGATE_BY_PK_PREFIX_WITH_SELECTOR, comparator, clusteringPrefixSize); |
| this.selector = selector; |
| this.columns = columns; |
| } |
| |
| @Override |
| public GroupMaker newGroupMaker(GroupingState state) |
| { |
| return GroupMaker.newSelectorGroupMaker(comparator, clusteringPrefixSize, selector, columns, state); |
| } |
| } |
| |
| public static class Serializer |
| { |
| public void serialize(AggregationSpecification aggregationSpec, DataOutputPlus out, int version) throws IOException |
| { |
| out.writeByte(aggregationSpec.kind().ordinal()); |
| switch (aggregationSpec.kind()) |
| { |
| case AGGREGATE_EVERYTHING: |
| break; |
| case AGGREGATE_BY_PK_PREFIX: |
| out.writeUnsignedVInt32(((AggregateByPkPrefix) aggregationSpec).clusteringPrefixSize); |
| break; |
| case AGGREGATE_BY_PK_PREFIX_WITH_SELECTOR: |
| AggregateByPkPrefixWithSelector spec = (AggregateByPkPrefixWithSelector) aggregationSpec; |
| out.writeUnsignedVInt32(spec.clusteringPrefixSize); |
| Selector.serializer.serialize(spec.selector, out, version); |
| // Ideally we should serialize the columns but that will break backward compatibility. |
| // So for the moment we can rebuild the list from the prefix size as we know that there will be |
| // only one column and that its indice will be: clusteringPrefixSize - 1. |
| break; |
| default: |
| throw new AssertionError("Unknow aggregation kind: " + aggregationSpec.kind()); |
| } |
| } |
| |
| public AggregationSpecification deserialize(DataInputPlus in, int version, TableMetadata metadata) throws IOException |
| { |
| Kind kind = Kind.values()[in.readUnsignedByte()]; |
| switch (kind) |
| { |
| case AGGREGATE_EVERYTHING: |
| return AggregationSpecification.AGGREGATE_EVERYTHING; |
| case AGGREGATE_BY_PK_PREFIX: |
| return new AggregateByPkPrefix(metadata.comparator, in.readUnsignedVInt32()); |
| case AGGREGATE_BY_PK_PREFIX_WITH_SELECTOR: |
| int clusteringPrefixSize = in.readUnsignedVInt32(); |
| Selector selector = Selector.serializer.deserialize(in, version, metadata); |
| ColumnMetadata functionArgument = metadata.clusteringColumns().get(clusteringPrefixSize - 1); |
| return new AggregateByPkPrefixWithSelector(metadata.comparator, |
| clusteringPrefixSize, |
| selector, |
| Collections.singletonList(functionArgument)); |
| default: |
| throw new AssertionError("Unknow aggregation kind: " + kind); |
| } |
| } |
| |
| public long serializedSize(AggregationSpecification aggregationSpec, int version) |
| { |
| long size = TypeSizes.sizeof((byte) aggregationSpec.kind().ordinal()); |
| switch (aggregationSpec.kind()) |
| { |
| case AGGREGATE_EVERYTHING: |
| break; |
| case AGGREGATE_BY_PK_PREFIX: |
| size += TypeSizes.sizeofUnsignedVInt(((AggregateByPkPrefix) aggregationSpec).clusteringPrefixSize); |
| break; |
| case AGGREGATE_BY_PK_PREFIX_WITH_SELECTOR: |
| AggregateByPkPrefixWithSelector spec = (AggregateByPkPrefixWithSelector) aggregationSpec; |
| size += TypeSizes.sizeofUnsignedVInt(spec.clusteringPrefixSize); |
| size += Selector.serializer.serializedSize(spec.selector, version); |
| break; |
| default: |
| throw new AssertionError("Unknow aggregation kind: " + aggregationSpec.kind()); |
| } |
| return size; |
| } |
| } |
| } |