/*
* Licensed to CRATE Technology GmbH ("Crate") under one or more contributor
* license agreements. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership. Crate 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.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial agreement.
*/
package io.crate.operation.aggregation.impl;
import com.google.common.collect.ImmutableList;
import io.crate.Streamer;
import io.crate.metadata.FunctionIdent;
import io.crate.metadata.FunctionInfo;
import io.crate.operation.Input;
import io.crate.operation.aggregation.AggregationFunction;
import io.crate.operation.aggregation.AggregationState;
import io.crate.types.DataType;
import io.crate.types.DataTypes;
import io.crate.types.SetType;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import java.io.IOException;
import java.util.HashSet;
import java.util.Set;
public abstract class CollectSetAggregation<T extends Comparable<T>>
extends AggregationFunction<CollectSetAggregation.CollectSetAggState> {
public static final String NAME = "collect_set";
private final FunctionInfo info;
public static void register(AggregationImplModule mod) {
for (final DataType dataType : DataTypes.PRIMITIVE_TYPES) {
final Streamer<?> setStreamer = new SetType(dataType).streamer();
mod.register(
new CollectSetAggregation(
new FunctionInfo(new FunctionIdent(NAME,
ImmutableList.of(dataType)),
dataType, FunctionInfo.Type.AGGREGATE
)
) {
@Override
public CollectSetAggState newState() {
return new CollectSetAggState() {
@Override
public void readFrom(StreamInput in) throws IOException {
setValue(setStreamer.readValueFrom(in));
}
@Override
public void writeTo(StreamOutput out) throws IOException {
setStreamer.writeValueTo(out, value());
}
};
}
}
);
}
}
CollectSetAggregation(FunctionInfo info) {
this.info = info;
}
@Override
public FunctionInfo info() {
return info;
}
@Override
public boolean iterate(CollectSetAggState state, Input... args) {
state.add(args[0].value());
return true;
}
public static abstract class CollectSetAggState extends AggregationState<CollectSetAggState> {
private Set<Object> value = new HashSet<>();
@Override
public Set value() {
return value;
}
@Override
public void reduce(CollectSetAggState other) {
value.addAll(other.value());
}
void add(Object otherValue) {
// ignore null values? yes
if (otherValue != null) {
value.add(otherValue);
}
}
public void setValue(Object value) {
this.value = (Set)value;
}
@Override
public int compareTo(CollectSetAggState o) {
if (o == null) return -1;
return compareValue(o.value);
}
public int compareValue(Set otherValue) {
return value.size() < otherValue.size() ? -1 : value.size() == otherValue.size() ? 0 : 1;
}
@Override
public String toString() {
return "<CollectSetAggState \"" + value + "\"";
}
}
}