content: /*
   * Copyright (C) 2011 Clearspring Technologies, 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.clearspring.analytics.stream.cardinality;
  
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Random;
  
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.Parameterized;
  import org.junit.runners.Parameterized.Parameters;
  
  import static org.junit.Assert.assertFalse;
  
  @RunWith(Parameterized.class)
  public class TestICardinality {
  
      private int N = 1000000;
      private ICardinality cardinalityEstimator;
      private static Random prng = new Random();
      private static char[] hex = "0123456789abcdef".toCharArray();
  
      public TestICardinality(ICardinality cardinalityEstimator) {
          super();
          this.cardinalityEstimator = cardinalityEstimator;
      }
  
      @Test
      public void testOffer() {
          cardinalityEstimator.offer("A");
          cardinalityEstimator.offer("B");
          cardinalityEstimator.offer("C");
          assertFalse(cardinalityEstimator.offer("C"));
          assertFalse(cardinalityEstimator.offer("B"));
          assertFalse(cardinalityEstimator.offer("A"));
          cardinalityEstimator.offer("ABCCBA");
          cardinalityEstimator.offer("CBAABC");
          cardinalityEstimator.offer("ABCABC");
          cardinalityEstimator.offer("CBACBA");
          assertFalse(cardinalityEstimator.offer("ABCCBA"));
      }
  
      @Test
      public void testICardinality() {
          System.out.println("size: " + cardinalityEstimator.sizeof() + " bytes");
          for (int i = 0; i < N; i++) {
              cardinalityEstimator.offer(streamElement(i));
          }
  
          long estimate = cardinalityEstimator.cardinality();
          System.out.println(estimate);
          double err = Math.abs(estimate - N) / (double) N;
          System.out.println("% Error: " + err * 100);
      }
  
      static int se = 0;
  
      public static Object streamElement(int i) {
          return Long.toHexString(prng.nextLong());
          //return se++;
      }
  
      @Parameters
      public static Collection<Object[]> regExValues() {
          return Arrays.asList(new Object[][]{
                  //{ new LinearCounting(65536) }, 
                  //{ new CountThenEstimate() },
                  {new AdaptiveCounting(16)},
                  //{ new LogLog(10) },
                  //{ new LogLog(12) }, 
                  //{ new LogLog(14) },
          });
      }
  
  }
  