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/*
 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */
package org.openjdk.jmh.samples;

import org.openjdk.jmh.annotations.AuxCounters;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Level;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.RunnerException;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;

import java.util.concurrent.TimeUnit;

@OutputTimeUnit(TimeUnit.SECONDS)
@Warmup(iterations = 5, time = 100, timeUnit = TimeUnit.MILLISECONDS)
@Measurement(iterations = 5, time = 100, timeUnit = TimeUnit.MILLISECONDS)
@Fork(1)
public class JMHSample_23_AuxCounters {

    /*
     * In some weird cases you need to get the separate throughput/time
     * metrics for the benchmarked code depending on the outcome of the
     * current code. Trying to accommodate the cases like this, JMH optionally
     * provides the special annotation which treats @State objects
     * as the object bearing user counters. See @AuxCounters javadoc for
     * the limitations.
     */

    @AuxCounters
    @State(Scope.Thread)
    public static class AdditionalCounters {
        public int case1, case2;

        @Setup(Level.Iteration)
        public void clean() {
            case1 = case2 = 0;
        }

        public int total() {
            return case1 + case2;
        }
    }

    /*
     * This code measures the "throughput" in two parts of the branch.
     * The @AuxCounters state above holds the counters which we increment
     * ourselves, and then let JMH to use their values in the performance
     * calculations. Note how we reset the counters on each iteration.
     */

    @Benchmark
    public void measure(AdditionalCounters counters) {
        if (Math.random() < 0.1) {
            counters.case1++;
        } else {
            counters.case2++;
        }
    }

    /*
     * ============================== HOW TO RUN THIS TEST: ====================================
     *
     * You can run this test:
     *
     * a) Via the command line:
     *    $ mvn clean install
     *    $ java -jar target/benchmarks.jar ".*JMHSample_23.*"
     *
     * b) Via the Java API:
     *    (see the JMH homepage for possible caveats when running from IDE:
     *      http://openjdk.java.net/projects/code-tools/jmh/)
     */

    public static void main(String[] args) throws RunnerException {
        Options opt = new OptionsBuilder()
                .include(".*" + JMHSample_23_AuxCounters.class.getSimpleName() + ".*")
                .build();

        new Runner(opt).run();
    }

}