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.beam.sdk.transforms;
  
  import static org.junit.Assert.assertEquals;
  
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import org.joda.time.Instant;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests of Min, Max, Mean, and Sum. */
  @RunWith(JUnit4.class)
  public class SimpleStatsFnsTest {
    static final double DOUBLE_COMPARISON_ACCURACY = 1e-7;
  
    private static class TestCase<NumT extends Number & Comparable<NumT>> {
      final List<NumT> data;
      final NumT min;
      final NumT max;
      final NumT sum;
      final Double mean;
  
      @SafeVarargs
      @SuppressWarnings("all")
      public TestCase(NumT min, NumT max, NumT sum, NumT... values) {
        this.data = Arrays.asList(values);
        this.min = min;
        this.max = max;
        this.sum = sum;
        this.mean = values.length == 0 ? Double.NaN : sum.doubleValue() / values.length;
      }
    }
  
    static final List<TestCase<Double>> DOUBLE_CASES =
        Arrays.asList(
            new TestCase<>(
                -312.31, 6312.31, 11629.13, -312.31, 29.13, 112.158, 6312.31, -312.158, -312.158,
                112.158, -312.31, 6312.31, 0.0),
            new TestCase<>(3.14, 3.14, 3.14, 3.14),
            new TestCase<>(Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY, 0.0));
  
    static final List<TestCase<Long>> LONG_CASES =
        Arrays.asList(
            new TestCase<>(
                -50000000000000000L,
                70000000000000000L,
                60000033123213121L,
                0L,
                1L,
                10000000000000000L,
                -50000000000000000L,
                70000000000000000L,
                0L,
                10000000000000000L,
                -1L,
                -50000000000000000L,
                70000000000000000L,
                33123213121L),
            new TestCase<>(3L, 3L, 3L, 3L),
            new TestCase<>(Long.MAX_VALUE, Long.MIN_VALUE, 0L));
  
    static final List<TestCase<Integer>> INTEGER_CASES =
        Arrays.asList(
            new TestCase<>(-3, 6, 22, 1, -3, 2, 6, 3, 4, -3, 5, 6, 1),
            new TestCase<>(3, 3, 3, 3),
            new TestCase<>(Integer.MAX_VALUE, Integer.MIN_VALUE, 0));
  
    @Test
    public void testInstantStats() {
      assertEquals(
          new Instant(1000),
          Min.<Instant>naturalOrder().apply(Arrays.asList(new Instant(1000), new Instant(2000))));
      assertEquals(null, Min.<Instant>naturalOrder().apply(Collections.emptyList()));
      assertEquals(
          new Instant(5000), Min.naturalOrder(new Instant(5000)).apply(Collections.emptyList()));
  
      assertEquals(
          new Instant(2000),
          Max.<Instant>naturalOrder().apply(Arrays.asList(new Instant(1000), new Instant(2000))));
      assertEquals(null, Max.<Instant>naturalOrder().apply(Collections.emptyList()));
      assertEquals(
          new Instant(5000), Max.naturalOrder(new Instant(5000)).apply(Collections.emptyList()));
    }
  
    @Test
    public void testDoubleStats() {
      for (TestCase<Double> t : DOUBLE_CASES) {
        assertEquals(t.sum, Sum.ofDoubles().apply(t.data), DOUBLE_COMPARISON_ACCURACY);
        assertEquals(t.min, Min.ofDoubles().apply(t.data), DOUBLE_COMPARISON_ACCURACY);
        assertEquals(t.max, Max.ofDoubles().apply(t.data), DOUBLE_COMPARISON_ACCURACY);
        assertEquals(t.mean, Mean.<Double>of().apply(t.data), DOUBLE_COMPARISON_ACCURACY);
      }
    }
  
    @Test
    public void testIntegerStats() {
      for (TestCase<Integer> t : INTEGER_CASES) {
        assertEquals(t.sum, Sum.ofIntegers().apply(t.data));
        assertEquals(t.min, Min.ofIntegers().apply(t.data));
        assertEquals(t.max, Max.ofIntegers().apply(t.data));
        assertEquals(t.mean, Mean.<Integer>of().apply(t.data));
      }
    }
  
    @Test
    public void testLongStats() {
      for (TestCase<Long> t : LONG_CASES) {
        assertEquals(t.sum, Sum.ofLongs().apply(t.data));
        assertEquals(t.min, Min.ofLongs().apply(t.data));
        assertEquals(t.max, Max.ofLongs().apply(t.data));
        assertEquals(t.mean, Mean.<Long>of().apply(t.data));
      }
    }
  }
  