sched/src/com/android/sched/util/log/stats/SampleImpl.java

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * 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.android.sched.util.log.stats;

import com.google.common.collect.Iterators;

import com.android.sched.util.table.DataHeader;
import com.android.sched.util.table.DataRow;

import java.util.Iterator;

import javax.annotation.CheckForNull;
import javax.annotation.Nonnegative;
import javax.annotation.Nonnull;

/**
 * Simple statistic computation on a set of values.
 */
public class SampleImpl extends Sample implements DataRow, DataHeader {
  @Nonnegative
  private int    count;

  private double min = Double.POSITIVE_INFINITY;
  @CheckForNull
  private Object minObject;

  private double max = Double.NEGATIVE_INFINITY;
  @CheckForNull
  private Object maxObject;
  private double total;

  protected SampleImpl(@Nonnull StatisticId<? extends Statistic> id) {
    super(id);
  }

  @Override
  public synchronized void add(double value, @CheckForNull Object obj) {
    if (!Double.isNaN(value)) {
      if (value < min) {
        min = value;
        minObject = obj;
      }
      if (value > max) {
        max = value;
        maxObject = obj;
      }

      total += value;
    }

    count++;
  }


  @Override
  @Nonnegative
  public int getCount() {
    return count;
  }

  @Override
  public double getTotal() {
    return total;
  }

  @Override
  public double getMin() {
    return min;
  }

  @Override
  public synchronized double getAverage() {
    return total / count;
  }

  @Override
  public double getMax() {
    return max;
  }

  @Override
  @CheckForNull
  public Object getMinObject() {
    return minObject;

  }

  @Override
  @CheckForNull
  public Object getMaxObject() {
    return maxObject;
  }

  @Override
  public synchronized void merge(@Nonnull Statistic statistic) {
    SampleImpl samples = (SampleImpl) statistic;

    this.count += samples.count;
    this.total += samples.total;
    if (samples.min < this.min) {
      this.min = samples.min;
      this.minObject = samples.minObject;
    }
    if (samples.max > this.max) {
      this.max = samples.max;
      this.maxObject = samples.maxObject;
    }
  }

  @Nonnull
  @Override
  public synchronized Iterator<Object> iterator() {
    return Iterators.forArray(
        Integer.valueOf(getCount()),
        Double.valueOf(getTotal()),
        Double.valueOf(getMin()),
        Double.valueOf(getAverage()),
        Double.valueOf(getMax()),
        getMinObject(),
        getMaxObject());
  }
}