Simple, slow but very short. :-) (#240)

* Simple, slow but very short. :-)

* Fix sync on DSS::accept.

calculate_average_alesj.sh

@@ -0,0 +1,23 @@
+#!/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.
+#
+
+# Uncomment below to use sdk
+# source "$HOME/.sdkman/bin/sdkman-init.sh"
+# sdk use java 21.0.1-graal 1>&2
+
+JAVA_OPTS=""
+time java $JAVA_OPTS --class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CalculateAverage_alesj

src/main/java/dev/morling/onebrc/CalculateAverage_alesj.java

@@ -0,0 +1,46 @@
+/*
+ *  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));
+    }
+}