/***********************************************************************************************************************
*
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* Licensed 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 eu.stratosphere.api.java.operators.translation;
import eu.stratosphere.api.java.functions.MapFunction;
import eu.stratosphere.api.java.tuple.Tuple;
import eu.stratosphere.api.java.tuple.Tuple2;
public final class TupleKeyExtractingMapper<T, K> extends MapFunction<T, Tuple2<K, T>> {
private static final long serialVersionUID = 1L;
private final int pos;
private final Tuple2<K, T> tuple = new Tuple2<K, T>();
public TupleKeyExtractingMapper(int pos) {
this.pos = pos;
}
@Override
public Tuple2<K, T> map(T value) throws Exception {
Tuple v = (Tuple) value;
K key = v.getField(pos);
tuple.f0 = key;
tuple.f1 = value;
return tuple;
}
}