001/* 002 * Java Genetic Algorithm Library (jenetics-8.0.0). 003 * Copyright (c) 2007-2024 Franz Wilhelmstötter 004 * 005 * Licensed under the Apache License, Version 2.0 (the "License"); 006 * you may not use this file except in compliance with the License. 007 * You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 * 017 * Author: 018 * Franz Wilhelmstötter (franz.wilhelmstoetter@gmail.com) 019 */ 020package io.jenetics.internal.util; 021 022import java.util.Iterator; 023import java.util.concurrent.CancellationException; 024import java.util.concurrent.CompletionException; 025import java.util.concurrent.ExecutionException; 026import java.util.concurrent.Future; 027 028/** 029 * Helper method for handĺing future objects. 030 * 031 * @author <a href="mailto:franz.wilhelmstoetter@gmail.com">Franz Wilhelmstötter</a> 032 * @version 8.0 033 * @since 8.0 034 */ 035public final class Futures { 036 private Futures() { 037 } 038 039 /** 040 * Joins the given set of futures. 041 * 042 * @param futures the future objects to join. 043 */ 044 public static void join(final Iterable<? extends Future<?>> futures) { 045 final Iterator<? extends Future<?>> tasks = futures.iterator(); 046 047 Exception exception = null; 048 Future<?> future = null; 049 try { 050 while (tasks.hasNext()) { 051 future = tasks.next(); 052 future.get(); 053 } 054 future = null; 055 } catch (InterruptedException | 056 ExecutionException | 057 CancellationException e) 058 { 059 exception = e; 060 } 061 062 // Cancel all remaining tasks, in case of an error. 063 if (future != null) { 064 future.cancel(true); 065 tasks.forEachRemaining(t -> t.cancel(true)); 066 } 067 068 // Handle exceptions, if any. 069 if (exception instanceof InterruptedException ie) { 070 Thread.currentThread().interrupt(); 071 final var ce = new CancellationException(ie.getMessage()); 072 ce.initCause(ie); 073 throw ce; 074 } else if (exception instanceof CancellationException e) { 075 throw e; 076 } else if (exception != null) { 077 throw new CompletionException(exception); 078 } 079 } 080 081}