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/*
* 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.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.concurrent.ConcurrentSkipListMap;
import java.util.stream.Collectors;
public class CalculateAverage_naive {
record Result(double min, double max, double sum, long count) {
}
public static void main(String[] args) throws FileNotFoundException {
long start = System.currentTimeMillis();
var results = new BufferedReader(new FileReader("./measurements.txt"))
.lines()
.map(l -> l.split(";"))
.collect(Collectors.toMap(
parts -> parts[0],
parts -> {
double temperature = Double.parseDouble(parts[1]);
return new Result(temperature, temperature, temperature, 1);
},
(oldResult, newResult) -> {
double min = Math.min(oldResult.min, newResult.min);
double max = Math.max(oldResult.max, newResult.max);
double sum = oldResult.sum + newResult.sum;
long count = oldResult.count + newResult.count;
return new Result(min, max, sum, count);
}, ConcurrentSkipListMap::new));
System.out.println(System.currentTimeMillis() - start);
System.out.println(results);
}
}
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