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Core Calcite APIs and engine.
/*
* 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.calcite.rel;
import org.apache.calcite.plan.RelMultipleTrait;
import org.apache.calcite.plan.RelOptPlanner;
import org.apache.calcite.plan.RelTrait;
import org.apache.calcite.util.ImmutableIntList;
import org.apache.calcite.util.Util;
import org.apache.calcite.util.mapping.Mapping;
import org.apache.calcite.util.mapping.Mappings;
import com.google.common.collect.Ordering;
import java.util.Collection;
import java.util.List;
import java.util.Objects;
import javax.annotation.Nonnull;
/**
* Utilities concerning {@link org.apache.calcite.rel.RelDistribution}.
*/
public class RelDistributions {
private static final ImmutableIntList EMPTY = ImmutableIntList.of();
/** The singleton singleton distribution. */
public static final RelDistribution SINGLETON =
new RelDistributionImpl(RelDistribution.Type.SINGLETON, EMPTY);
/** The singleton random distribution. */
public static final RelDistribution RANDOM_DISTRIBUTED =
new RelDistributionImpl(RelDistribution.Type.RANDOM_DISTRIBUTED, EMPTY);
/** The singleton round-robin distribution. */
public static final RelDistribution ROUND_ROBIN_DISTRIBUTED =
new RelDistributionImpl(RelDistribution.Type.ROUND_ROBIN_DISTRIBUTED,
EMPTY);
/** The singleton broadcast distribution. */
public static final RelDistribution BROADCAST_DISTRIBUTED =
new RelDistributionImpl(RelDistribution.Type.BROADCAST_DISTRIBUTED,
EMPTY);
public static final RelDistribution ANY =
new RelDistributionImpl(RelDistribution.Type.ANY, EMPTY);
private RelDistributions() {}
/** Creates a hash distribution. */
public static RelDistribution hash(Collection numbers) {
ImmutableIntList list = ImmutableIntList.copyOf(numbers);
if (numbers.size() > 1
&& !Ordering.natural().isOrdered(list)) {
list = ImmutableIntList.copyOf(Ordering.natural().sortedCopy(list));
}
RelDistributionImpl trait =
new RelDistributionImpl(RelDistribution.Type.HASH_DISTRIBUTED, list);
return RelDistributionTraitDef.INSTANCE.canonize(trait);
}
/** Creates a range distribution. */
public static RelDistribution range(Collection numbers) {
ImmutableIntList list = ImmutableIntList.copyOf(numbers);
RelDistributionImpl trait =
new RelDistributionImpl(RelDistribution.Type.RANGE_DISTRIBUTED, list);
return RelDistributionTraitDef.INSTANCE.canonize(trait);
}
/** Implementation of {@link org.apache.calcite.rel.RelDistribution}. */
private static class RelDistributionImpl implements RelDistribution {
private static final Ordering> ORDERING =
Ordering.natural().lexicographical();
private final Type type;
private final ImmutableIntList keys;
private RelDistributionImpl(Type type, ImmutableIntList keys) {
this.type = Objects.requireNonNull(type);
this.keys = ImmutableIntList.copyOf(keys);
assert type != Type.HASH_DISTRIBUTED
|| keys.size() < 2
|| Ordering.natural().isOrdered(keys)
: "key columns of hash distribution must be in order";
assert type == Type.HASH_DISTRIBUTED
|| type == Type.RANDOM_DISTRIBUTED
|| keys.isEmpty();
}
@Override public int hashCode() {
return Objects.hash(type, keys);
}
@Override public boolean equals(Object obj) {
return this == obj
|| obj instanceof RelDistributionImpl
&& type == ((RelDistributionImpl) obj).type
&& keys.equals(((RelDistributionImpl) obj).keys);
}
@Override public String toString() {
if (keys.isEmpty()) {
return type.shortName;
} else {
return type.shortName + keys;
}
}
@Nonnull public Type getType() {
return type;
}
@Nonnull public List getKeys() {
return keys;
}
public RelDistributionTraitDef getTraitDef() {
return RelDistributionTraitDef.INSTANCE;
}
public RelDistribution apply(Mappings.TargetMapping mapping) {
if (keys.isEmpty()) {
return this;
}
return getTraitDef().canonize(
new RelDistributionImpl(type,
ImmutableIntList.copyOf(
Mappings.apply((Mapping) mapping, keys))));
}
public boolean satisfies(RelTrait trait) {
if (trait == this || trait == ANY) {
return true;
}
if (trait instanceof RelDistributionImpl) {
RelDistributionImpl distribution = (RelDistributionImpl) trait;
if (type == distribution.type) {
switch (type) {
case HASH_DISTRIBUTED:
// The "leading edge" property of Range does not apply to Hash.
// Only Hash[x, y] satisfies Hash[x, y].
return keys.equals(distribution.keys);
case RANGE_DISTRIBUTED:
// Range[x, y] satisfies Range[x, y, z] but not Range[x]
return Util.startsWith(distribution.keys, keys);
default:
return true;
}
}
}
if (trait == RANDOM_DISTRIBUTED) {
// RANDOM is satisfied by HASH, ROUND-ROBIN, RANDOM, RANGE;
// we've already checked RANDOM
return type == Type.HASH_DISTRIBUTED
|| type == Type.ROUND_ROBIN_DISTRIBUTED
|| type == Type.RANGE_DISTRIBUTED;
}
return false;
}
public void register(RelOptPlanner planner) {
}
@Override public boolean isTop() {
return type == Type.ANY;
}
@Override public int compareTo(@Nonnull RelMultipleTrait o) {
final RelDistribution distribution = (RelDistribution) o;
if (type == distribution.getType()
&& (type == Type.HASH_DISTRIBUTED
|| type == Type.RANGE_DISTRIBUTED)) {
return ORDERING.compare(getKeys(), distribution.getKeys());
}
return type.compareTo(distribution.getType());
}
}
}
// End RelDistributions.java