/*
* 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.java.functions.FunctionAnnotation.ForwardedFields;
import org.apache.flink.api.java.functions.KeySelector;
import org.apache.flink.api.common.functions.RichMapFunction;
import org.apache.flink.api.java.tuple.Tuple2;
@Internal
@ForwardedFields("*->1")
public final class KeyExtractingMapper<T, K> extends RichMapFunction<T, Tuple2<K, T>> {
private static final long serialVersionUID = 1L;
private final KeySelector<T, K> keySelector;
private final Tuple2<K, T> tuple = new Tuple2<K, T>();
public KeyExtractingMapper(KeySelector<T, K> keySelector) {
this.keySelector = keySelector;
}
@Override
public Tuple2<K, T> map(T value) throws Exception {
K key = keySelector.getKey(value);
tuple.f0 = key;
tuple.f1 = value;
return tuple;
}
}