/*
* 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.api.common.functions.CombineFunction;
import org.apache.flink.api.common.functions.GroupCombineFunction;
import org.apache.flink.api.common.functions.GroupReduceFunction;
import org.apache.flink.api.common.functions.RichGroupCombineFunction;
import org.apache.flink.api.common.functions.RichGroupReduceFunction;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.util.Collector;
import org.apache.flink.util.Preconditions;
/**
* A wrapper the wraps a function that implements both {@link CombineFunction} and {@link GroupReduceFunction} interfaces
* and makes it look like a function that implements {@link GroupCombineFunction} and {@link GroupReduceFunction} to the runtime.
*/
public class RichCombineToGroupCombineWrapper<IN, OUT, F extends RichGroupReduceFunction<IN, OUT> & CombineFunction<IN, IN>>
extends RichGroupCombineFunction<IN,IN> implements GroupReduceFunction<IN, OUT> {
private final F wrappedFunction;
public RichCombineToGroupCombineWrapper(F wrappedFunction) {
this.wrappedFunction = Preconditions.checkNotNull(wrappedFunction);
}
@Override
public void open(Configuration config) throws Exception {
wrappedFunction.open(config);
}
@Override
public void combine(Iterable<IN> values, Collector<IN> out) throws Exception {
IN outValue = wrappedFunction.combine(values);
out.collect(outValue);
}
@Override
public void reduce(Iterable<IN> values, Collector<OUT> out) throws Exception {
wrappedFunction.reduce(values, out);
}
}