caliper/src/main/java/com/google/caliper/worker/MacrobenchmarkWorker.java

/*
 * Copyright (C) 2013 Google Inc.
 *
 * 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 com.google.caliper.worker;

import static com.google.caliper.util.Reflection.getAnnotatedMethods;
import static java.util.concurrent.TimeUnit.NANOSECONDS;

import com.google.caliper.api.AfterRep;
import com.google.caliper.api.BeforeRep;
import com.google.caliper.model.Measurement;
import com.google.caliper.model.Value;
import com.google.caliper.runner.Running.Benchmark;
import com.google.caliper.runner.Running.BenchmarkMethod;
import com.google.caliper.util.Util;
import com.google.common.base.Stopwatch;
import com.google.common.base.Ticker;
import com.google.common.collect.ImmutableSet;

import java.lang.reflect.Method;
import java.util.Map;

import javax.inject.Inject;

/**
 * The {@link Worker} implementation for macrobenchmarks.
 */
public class MacrobenchmarkWorker extends Worker {
  private final Stopwatch stopwatch;
  private final ImmutableSet<Method> beforeRepMethods;
  private final ImmutableSet<Method> afterRepMethods;
  private final boolean gcBeforeEach;

  @Inject MacrobenchmarkWorker(@Benchmark Object benchmark, @BenchmarkMethod Method method,
      Ticker ticker, @WorkerOptions Map<String, String> workerOptions) {
    super(benchmark, method);
    this.stopwatch = Stopwatch.createUnstarted(ticker);
    this.beforeRepMethods =
        getAnnotatedMethods(benchmark.getClass(), BeforeRep.class);
    this.afterRepMethods =
        getAnnotatedMethods(benchmark.getClass(), AfterRep.class);
    this.gcBeforeEach = Boolean.parseBoolean(workerOptions.get("gcBeforeEach"));
  }

  @Override public void preMeasure(boolean inWarmup) throws Exception {
    for (Method beforeRepMethod : beforeRepMethods) {
      beforeRepMethod.invoke(benchmark);
    }
    if (gcBeforeEach && !inWarmup) {
      Util.forceGc();
    }
  }

  @Override public Iterable<Measurement> measure() throws Exception {
    stopwatch.start();
    benchmarkMethod.invoke(benchmark);
    long nanos = stopwatch.stop().elapsed(NANOSECONDS);
    stopwatch.reset();
    return ImmutableSet.of(new Measurement.Builder()
        .description("runtime")
        .weight(1)
        .value(Value.create(nanos, "ns"))
        .build());
  }

  @Override public void postMeasure() throws Exception {
    for (Method afterRepMethod : afterRepMethods) {
      afterRepMethod.invoke(benchmark);
    }
  }
}