1brc/src/main/java/dev/morling/onebrc/CalculateAverage_alesj.java
Aleš Justin 965e852ba7
Simple, slow but very short. :-) (#240)
* Simple, slow but very short. :-)

* Fix sync on DSS::accept.
2024-01-11 09:48:27 +01:00

47 lines
1.8 KiB
Java

/*
* 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<String, DoubleSummaryStatistics> stations = new ConcurrentHashMap<>();
try (Stream<String> 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));
}
}