From 95c9d091ef0083285410231bb202d203e0336cf1 Mon Sep 17 00:00:00 2001 From: Karl Heinz Marbaise Date: Wed, 3 Jan 2024 20:21:23 +0100 Subject: Adding khmarbaise --- .../onebrc/CalculateAverage_khmarbaise.java | 61 ++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 src/main/java/dev/morling/onebrc/CalculateAverage_khmarbaise.java (limited to 'src/main/java/dev/morling') diff --git a/src/main/java/dev/morling/onebrc/CalculateAverage_khmarbaise.java b/src/main/java/dev/morling/onebrc/CalculateAverage_khmarbaise.java new file mode 100644 index 0000000..9bcf0a9 --- /dev/null +++ b/src/main/java/dev/morling/onebrc/CalculateAverage_khmarbaise.java @@ -0,0 +1,61 @@ +/* + * 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.io.IOException; +import java.nio.file.Files; +import java.nio.file.Path; +import java.util.DoubleSummaryStatistics; +import java.util.Map; +import java.util.function.Function; +import java.util.stream.Collectors; +import java.util.stream.Stream; + +import static java.util.stream.Collectors.groupingBy; + +public class CalculateAverage_khmarbaise { + + private static final Path MEASUREMENT_FILES = Path.of("./measurements.txt"); + + private record MeasurementRecord(String city, Double measuredValue) { + } + + private static final Function toMeasurementRecord = line -> { + var posOf = line.indexOf(";"); + var city = line.substring(0, posOf); + var measuredValue = line.substring(posOf + 1); + return new MeasurementRecord(city, Double.parseDouble(measuredValue)); + }; + + private static final Function, String> MIN_AVG_MAX = s -> String.format("%s=%.1f/%.1f/%.1f", s.getKey(), + s.getValue().getMin(), s.getValue().getAverage(), s.getValue().getMax()); + + public static void main(String[] args) throws IOException { + try (Stream lines = Files.lines(MEASUREMENT_FILES)) { + var collect = lines + .parallel() + .map(toMeasurementRecord) + .collect(groupingBy(MeasurementRecord::city, Collectors.summarizingDouble(MeasurementRecord::measuredValue))) + .entrySet() + .stream() + .sorted(Map.Entry.comparingByKey()) + .map(MIN_AVG_MAX) + .collect(Collectors.joining(", ")); + + System.out.println("{" + collect + "}"); + } + } +} -- cgit v1.2.3