| /* |
| * 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.wayang.flink.compiler; |
| |
| import java.io.Serializable; |
| import java.util.function.Function; |
| import org.apache.flink.api.common.typeinfo.TypeInformation; |
| import org.apache.flink.api.java.functions.KeySelector; |
| import org.apache.flink.api.java.typeutils.ResultTypeQueryable; |
| import org.apache.wayang.core.function.TransformationDescriptor; |
| |
| /** |
| * Wrapper for {@Link KeySelector} |
| */ |
| public class KeySelectorFunction<T, K> implements KeySelector<T, K>, ResultTypeQueryable<K>, Serializable { |
| |
| public Function<T, K> impl; |
| |
| public Class<K> key; |
| |
| public TypeInformation<K> typeInformation; |
| |
| public KeySelectorFunction(TransformationDescriptor<T, K> transformationDescriptor) { |
| |
| this.impl = transformationDescriptor.getJavaImplementation(); |
| this.key = transformationDescriptor.getOutputType().getTypeClass(); |
| this.typeInformation = TypeInformation.of(this.key); |
| } |
| |
| public K getKey(T object){ |
| return this.impl.apply(object); |
| } |
| |
| @Override |
| public TypeInformation getProducedType() { |
| return this.typeInformation; |
| } |
| } |