java/function/CoGroupFunction.java

0001 /*
0002  * Licensed to the Apache Software Foundation (ASF) under one or more
0003  * contributor license agreements.  See the NOTICE file distributed with
0004  * this work for additional information regarding copyright ownership.
0005  * The ASF licenses this file to You under the Apache License, Version 2.0
0006  * (the "License"); you may not use this file except in compliance with
0007  * the License.  You may obtain a copy of the License at
0008  *
0009  *    http://www.apache.org/licenses/LICENSE-2.0
0010  *
0011  * Unless required by applicable law or agreed to in writing, software
0012  * distributed under the License is distributed on an "AS IS" BASIS,
0013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0014  * See the License for the specific language governing permissions and
0015  * limitations under the License.
0016  */
0017
0018 package org.apache.spark.api.java.function;
0019
0020 import java.io.Serializable;
0021 import java.util.Iterator;
0022
0023 /**
0024  * A function that returns zero or more output records from each grouping key and its values from 2
0025  * Datasets.
0026  */
0027 @FunctionalInterface
0028 public interface CoGroupFunction<K, V1, V2, R> extends Serializable {
0029   Iterator<R> call(K key, Iterator<V1> left, Iterator<V2> right) throws Exception;
0030 }