001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019package org.apache.reef.io.network.group.api.operators; 020 021import org.apache.reef.exception.evaluator.NetworkException; 022import org.apache.reef.wake.Identifier; 023 024import java.util.List; 025 026/** 027 * MPI AllGather Operator. 028 * <p> 029 * Each task applies this operator on an element of type T. The result will be 030 * a list of elements constructed using the elements all-gathered at each 031 * task. 032 */ 033public interface AllGather<T> extends GroupCommOperator { 034 035 /** 036 * Apply the operation on element. 037 * 038 * @return List of all elements on which the operation was applied using default order 039 */ 040 List<T> apply(T element) throws NetworkException, 041 InterruptedException; 042 043 /** 044 * Apply the operation on element. 045 * 046 * @return List of all elements on which the operation was applied using order specified 047 */ 048 List<T> apply(T element, List<? extends Identifier> order) 049 throws NetworkException, InterruptedException; 050}