| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.logging.log4j.perf.jmh; |
| |
| import org.apache.logging.log4j.core.time.MutableInstant; |
| import org.apache.logging.log4j.core.time.internal.format.FastDatePrinter; |
| import org.apache.logging.log4j.core.time.internal.format.FixedDateFormat; |
| import org.openjdk.jmh.annotations.Benchmark; |
| import org.openjdk.jmh.annotations.Scope; |
| import org.openjdk.jmh.annotations.State; |
| import org.openjdk.jmh.infra.Blackhole; |
| |
| import java.time.Instant; |
| import java.time.format.DateTimeFormatter; |
| import java.util.*; |
| import java.util.stream.IntStream; |
| |
| /** |
| * Compares {@link MutableInstant} formatting efficiency of |
| * {@link FastDatePrinter}, {@link FixedDateFormat}, and {@link DateTimeFormatter}. |
| * <p> |
| * The major formatting efficiency is mostly provided by caching, i.e., |
| * reusing the earlier formatter output if timestamps match. We deliberately |
| * exclude this optimization, since it is applicable to all formatters. This |
| * benchmark rather focuses on only and only the formatting efficiency. |
| */ |
| @State(Scope.Thread) |
| public class DateTimeFormatBenchmark { |
| |
| /** |
| * The pattern to be tested. |
| * <p> |
| * Note that neither {@link FastDatePrinter}, nor {@link FixedDateFormat} |
| * supports nanosecond precision. |
| */ |
| private static final String PATTERN = "yyyy-MM-dd'T'HH:mm:ss.SSS"; |
| |
| private static final Locale LOCALE = Locale.US; |
| |
| private static final TimeZone TIME_ZONE = TimeZone.getTimeZone("UTC"); |
| |
| private static final Instant INIT_INSTANT = Instant.parse("2020-05-14T10:44:23.901Z"); |
| |
| private static final MutableInstant[] INSTANTS = IntStream |
| .range(0, 1_000) |
| .mapToObj((final int index) -> { |
| final MutableInstant instant = new MutableInstant(); |
| instant.initFromEpochSecond( |
| Math.addExact(INIT_INSTANT.getEpochSecond(), index), |
| Math.addExact(INIT_INSTANT.getNano(), index)); |
| return instant; |
| }) |
| .toArray(MutableInstant[]::new); |
| |
| private static final Calendar[] CALENDARS = Arrays |
| .stream(INSTANTS) |
| .map((final MutableInstant instant) -> { |
| final Calendar calendar = Calendar.getInstance(TIME_ZONE, LOCALE); |
| calendar.setTimeInMillis(instant.getEpochMillisecond()); |
| return calendar; |
| }) |
| .toArray(Calendar[]::new); |
| |
| private static final FastDatePrinter FAST_DATE_PRINTER = |
| new FastDatePrinter(PATTERN, TIME_ZONE, LOCALE) {}; |
| |
| private static final FixedDateFormat FIXED_DATE_FORMAT = |
| Objects.requireNonNull( |
| FixedDateFormat.createIfSupported(PATTERN, TIME_ZONE.getID()), |
| "couldn't create FixedDateTime for pattern " + PATTERN + " and time zone " + TIME_ZONE.getID()); |
| |
| private static final DateTimeFormatter DATE_TIME_FORMATTER = |
| DateTimeFormatter |
| .ofPattern(PATTERN) |
| .withZone(TIME_ZONE.toZoneId()) |
| .withLocale(LOCALE); |
| |
| private final StringBuilder stringBuilder = new StringBuilder(PATTERN.length() * 2); |
| |
| private final char[] charBuffer = new char[stringBuilder.capacity()]; |
| |
| @Benchmark |
| public void fastDatePrinter(final Blackhole blackhole) { |
| for (final Calendar calendar : CALENDARS) { |
| stringBuilder.setLength(0); |
| FAST_DATE_PRINTER.format(calendar, stringBuilder); |
| blackhole.consume(stringBuilder.length()); |
| } |
| } |
| |
| @Benchmark |
| public void fixedDateFormat(final Blackhole blackhole) { |
| for (final MutableInstant instant : INSTANTS) { |
| final int length = FIXED_DATE_FORMAT.formatInstant(instant, charBuffer, 0); |
| blackhole.consume(length); |
| } |
| } |
| |
| @Benchmark |
| public void dateTimeFormatter(final Blackhole blackhole) { |
| for (final MutableInstant instant : INSTANTS) { |
| stringBuilder.setLength(0); |
| DATE_TIME_FORMATTER.formatTo(instant, stringBuilder); |
| blackhole.consume(stringBuilder.length()); |
| } |
| } |
| |
| } |