diff --git a/calculate_average_abfrmblr.sh b/calculate_average_abfrmblr.sh new file mode 100755 index 0000000..e0362e8 --- /dev/null +++ b/calculate_average_abfrmblr.sh @@ -0,0 +1,20 @@ +#!/bin/sh +# +# 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. +# + + +JAVA_OPTS="--enable-preview -Xms2g -Xmx2g" +time java $JAVA_OPTS --class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CalculateAverage_abfrmblr diff --git a/src/main/java/dev/morling/onebrc/CalculateAverage_abfrmblr.java b/src/main/java/dev/morling/onebrc/CalculateAverage_abfrmblr.java new file mode 100644 index 0000000..b153bd8 --- /dev/null +++ b/src/main/java/dev/morling/onebrc/CalculateAverage_abfrmblr.java @@ -0,0 +1,70 @@ +/* + * 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.util.concurrent.*; +import java.util.stream.Stream; + +import static java.nio.file.Files.lines; +import static java.nio.file.Paths.*; + +public class CalculateAverage_abfrmblr { + + private static final String FILE = "./measurements.txt"; + + private static record Stats (double min, double max, double mean, long count) { + @Override + public String toString() { + return round(min) + "/" + round(mean) + "/" + round(max); + } + private double round(double value) { + return Math.round(value * 10.0) / 10.0; + } + } + + private static record MeasurementTuple (String station, double temp) { + public MeasurementTuple (String[] values) { + this(values[0], Double.parseDouble(values[1])); + } + } + + public static void main(String[] args) throws IOException { + Stream lines = lines(get(FILE)); + + ConcurrentMap aggregatedStats = new ConcurrentSkipListMap<>(); + + lines.parallel().forEach(s -> { + MeasurementTuple tuple = new MeasurementTuple(s.split(";")); + aggregatedStats.compute(tuple.station(), (s1, stats) -> { + if (stats == null) { + return new Stats(tuple.temp, tuple.temp, tuple.temp, 1L); + } + else { + long latestCount = stats.count + 1; + double min = Math.min(stats.min, tuple.temp); + double max = Math.max(stats.max, tuple.temp); + double mean = ((stats.mean * stats.count) + tuple.temp) / latestCount; + return new Stats(min, max, mean, latestCount); + } + }); + }); + + System.out.println(aggregatedStats); + + } + +}