content: /*
   * 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.kafka.trogdor.workload;
  
  import org.junit.jupiter.api.Test;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  
  public class HistogramTest {
      private static Histogram createHistogram(int maxValue, int... values) {
          Histogram histogram = new Histogram(maxValue);
          for (int value : values) {
              histogram.add(value);
          }
          return histogram;
      }
  
      @Test
      public void testHistogramAverage() {
          Histogram empty = createHistogram(1);
          assertEquals(0, (int) empty.summarize(new float[0]).average());
  
          Histogram histogram = createHistogram(70, 1, 2, 3, 4, 5, 6, 1);
  
          assertEquals(3, (int) histogram.summarize(new float[0]).average());
          histogram.add(60);
          assertEquals(10, (int) histogram.summarize(new float[0]).average());
      }
  
      @Test
      public void testHistogramSamples() {
          Histogram empty = createHistogram(100);
          assertEquals(0, empty.summarize(new float[0]).numSamples());
          Histogram histogram = createHistogram(100, 4, 8, 2, 4, 1, 100, 150);
          assertEquals(7, histogram.summarize(new float[0]).numSamples());
          histogram.add(60);
          assertEquals(8, histogram.summarize(new float[0]).numSamples());
      }
  
      @Test
      public void testHistogramPercentiles() {
          Histogram histogram = createHistogram(100, 1, 2, 3, 4, 5, 6, 80, 90);
          float[] percentiles = new float[] {0.5f, 0.90f, 0.99f, 1f};
          Histogram.Summary summary = histogram.summarize(percentiles);
          assertEquals(8, summary.numSamples());
          assertEquals(4, summary.percentiles().get(0).value());
          assertEquals(80, summary.percentiles().get(1).value());
          assertEquals(80, summary.percentiles().get(2).value());
          assertEquals(90, summary.percentiles().get(3).value());
          histogram.add(30);
          histogram.add(30);
          histogram.add(30);
  
          summary = histogram.summarize(new float[] {0.5f});
          assertEquals(11, summary.numSamples());
          assertEquals(5, summary.percentiles().get(0).value());
  
          Histogram empty = createHistogram(100);
          summary = empty.summarize(new float[] {0.5f});
          assertEquals(0, summary.percentiles().get(0).value());
  
          histogram = createHistogram(1000);
          histogram.add(100);
          histogram.add(200);
          summary = histogram.summarize(new float[] {0f, 0.5f, 1.0f});
          assertEquals(0, summary.percentiles().get(0).value());
          assertEquals(100, summary.percentiles().get(1).value());
          assertEquals(200, summary.percentiles().get(2).value());
      }
  }
  