/*
* 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;
import org.apache.flink.annotation.Public;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.common.operators.Operator;
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.DataSet;
/**
* This operator represents the application of a "map" function on a data set, and the
* result data set produced by the function.
*
* @param <IN> The type of the data set consumed by the operator.
* @param <OUT> The type of the data set created by the operator.
*
* @see org.apache.flink.api.common.functions.MapFunction
*/
@Public
public class MapOperator<IN, OUT> extends SingleInputUdfOperator<IN, OUT, MapOperator<IN, OUT>> {
protected final MapFunction<IN, OUT> function;
protected final String defaultName;
public MapOperator(DataSet<IN> input, TypeInformation<OUT> resultType, MapFunction<IN, OUT> function, String defaultName) {
super(input, resultType);
this.defaultName = defaultName;
this.function = function;
UdfOperatorUtils.analyzeSingleInputUdf(this, MapFunction.class, defaultName, function, null);
}
@Override
protected MapFunction<IN, OUT> getFunction() {
return function;
}
@Override
protected MapOperatorBase<IN, OUT, MapFunction<IN, OUT>> translateToDataFlow(Operator<IN> input) {
String name = getName() != null ? getName() : "Map at "+defaultName;
// create operator
MapOperatorBase<IN, OUT, MapFunction<IN, OUT>> po = new MapOperatorBase<IN, OUT, MapFunction<IN, OUT>>(function,
new UnaryOperatorInformation<IN, OUT>(getInputType(), getResultType()), name);
// set input
po.setInput(input);
// set parallelism
if(this.getParallelism() > 0) {
// use specified parallelism
po.setParallelism(this.getParallelism());
} else {
// if no parallelism has been specified, use parallelism of input operator to enable chaining
po.setParallelism(input.getParallelism());
}
return po;
}
}