/* * Copyright 2023 The original authors * * Licensed 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 dev.morling.onebrc; import java.nio.file.Files; import java.nio.file.Paths; import java.util.DoubleSummaryStatistics; import java.util.Map; import java.util.TreeMap; import java.util.concurrent.ConcurrentHashMap; import java.util.stream.Stream; public class CalculateAverage_alesj { public static void main(String[] args) throws Exception { Map stations = new ConcurrentHashMap<>(); try (Stream stream = Files.lines(Paths.get("./measurements.txt")).parallel()) { stream.forEach(line -> { String[] split = line.split(";"); stations.computeIfAbsent(split[0], k -> new DoubleSummaryStatistics() { public synchronized void accept(double value) { super.accept(value); } public String toString() { return String.format("%.1f/%.1f/%.1f", getMin(), getAverage(), getMax()); } }) .accept(Double.parseDouble(split[1])); }); } System.out.println(new TreeMap<>(stations)); } }