/*
* 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.ExecutionConfig;
import org.apache.flink.api.common.functions.AbstractRichFunction;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.common.operators.UnaryOperatorInformation;
import org.apache.flink.api.common.operators.base.MapOperatorBase;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.java.tuple.Tuple;
@Internal
public class PlanProjectOperator<T, R extends Tuple> extends MapOperatorBase<T, R, MapFunction<T, R>> {
public PlanProjectOperator(int[] fields, String name,
TypeInformation<T> inType, TypeInformation<R> outType,
ExecutionConfig executionConfig)
{
super(PlanProjectOperator.<T, R, Tuple>createTypedProjector(fields), new UnaryOperatorInformation<T, R>(inType, outType), name);
}
@SuppressWarnings("unchecked")
private static <T, R extends Tuple, X extends Tuple> MapFunction<T, R> createTypedProjector(int[] fields) {
return (MapFunction<T, R>) new MapProjector<X, R>(fields);
}
public static final class MapProjector<T extends Tuple, R extends Tuple>
extends AbstractRichFunction implements MapFunction<T, R>
{
private static final long serialVersionUID = 1L;
private final int[] fields;
private final Tuple outTuple;
private MapProjector(int[] fields) {
this.fields = fields;
try {
this.outTuple = Tuple.getTupleClass(fields.length).newInstance();
}
catch (Exception e) {
// this should never happen
throw new RuntimeException(e);
}
}
// TODO We should use code generation for this.
@SuppressWarnings("unchecked")
@Override
public R map(Tuple inTuple) throws Exception {
for (int i = 0; i < fields.length; i++) {
outTuple.setField(inTuple.getField(fields[i]), i);
}
return (R) outTuple;
}
}
}