/*
* 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.flink.api.java.operators.translation;
import org.apache.flink.annotation.Internal;
import org.apache.flink.api.common.functions.GroupCombineFunction;
import org.apache.flink.api.common.operators.UnaryOperatorInformation;
import org.apache.flink.api.common.operators.base.GroupCombineOperatorBase;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.common.operators.Keys;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.util.Collector;
/**
* A group combine operator that takes 2-tuples (key-value pairs), and applies the group combine operation only
* on the unwrapped values.
*/
@Internal
public class PlanUnwrappingGroupCombineOperator<IN, OUT, K> extends GroupCombineOperatorBase<Tuple2<K, IN>, OUT, GroupCombineFunction<Tuple2<K, IN>, OUT>> {
public PlanUnwrappingGroupCombineOperator(GroupCombineFunction<IN, OUT> udf, Keys.SelectorFunctionKeys<IN, K> key, String name,
TypeInformation<OUT> outType, TypeInformation<Tuple2<K, IN>> typeInfoWithKey)
{
super(new TupleUnwrappingGroupCombiner<IN, OUT, K>(udf),
new UnaryOperatorInformation<Tuple2<K, IN>, OUT>(typeInfoWithKey, outType), key.computeLogicalKeyPositions(), name);
}
// --------------------------------------------------------------------------------------------
public static final class TupleUnwrappingGroupCombiner<IN, OUT, K> extends WrappingFunction<GroupCombineFunction<IN, OUT>>
implements GroupCombineFunction<Tuple2<K, IN>, OUT>
{
private static final long serialVersionUID = 1L;
private final TupleUnwrappingIterator<IN, K> iter;
private TupleUnwrappingGroupCombiner(GroupCombineFunction<IN, OUT> wrapped) {
super(wrapped);
this.iter = new TupleUnwrappingIterator<IN, K>();
}
@Override
public void combine(Iterable<Tuple2<K, IN>> values, Collector<OUT> out) throws Exception {
iter.set(values.iterator());
this.wrappedFunction.combine(iter, out);
}
@Override
public String toString() {
return this.wrappedFunction.toString();
}
}
}