View Javadoc
1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      https://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.text.similarity;
18  
19  import static org.junit.jupiter.api.Assertions.assertEquals;
20  import static org.junit.jupiter.api.Assertions.assertThrows;
21  
22  import org.junit.jupiter.api.BeforeAll;
23  import org.junit.jupiter.api.Test;
24  import org.junit.jupiter.params.ParameterizedTest;
25  import org.junit.jupiter.params.provider.MethodSource;
26  
27  /**
28   * Tests {@link HammingDistance}.
29   */
30  class HammingDistanceTest {
31  
32      private static HammingDistance distance;
33  
34      @BeforeAll
35      public static void setUp() {
36          distance = new HammingDistance();
37      }
38  
39      @ParameterizedTest
40      @MethodSource("org.apache.commons.text.similarity.SimilarityInputTest#similarityInputsEquals()")
41      void testHammingDistance(final Class<?> cls) {
42          assertEquals(0, distance.apply(SimilarityInputTest.build(cls, ""), SimilarityInputTest.build(cls, "")));
43          assertEquals(0, distance.apply(SimilarityInputTest.build(cls, "pappa"), SimilarityInputTest.build(cls, "pappa")));
44          assertEquals(1, distance.apply(SimilarityInputTest.build(cls, "papaa"), SimilarityInputTest.build(cls, "pappa")));
45          assertEquals(3, distance.apply(SimilarityInputTest.build(cls, "karolin"), SimilarityInputTest.build(cls, "kathrin")));
46          assertEquals(3, distance.apply(SimilarityInputTest.build(cls, "karolin"), SimilarityInputTest.build(cls, "kerstin")));
47          assertEquals(2, distance.apply(SimilarityInputTest.build(cls, "1011101"), SimilarityInputTest.build(cls, "1001001")));
48          assertEquals(3, distance.apply(SimilarityInputTest.build(cls, "2173896"), SimilarityInputTest.build(cls, "2233796")));
49          assertEquals(2, distance.apply(SimilarityInputTest.build(cls, "ATCG"), SimilarityInputTest.build(cls, "ACCC")));
50      }
51  
52      @Test
53      void testHammingDistance_nullLeftValue() {
54          assertThrows(IllegalArgumentException.class, () -> distance.apply(null, ""));
55      }
56  
57      @Test
58      void testHammingDistance_nullRightValue() {
59          assertThrows(IllegalArgumentException.class, () -> distance.apply("", null));
60      }
61  
62      @Test
63      void testHammingDistanceCharSequence() {
64          assertEquals(0, distance.apply("", ""));
65          assertEquals(0, distance.apply("pappa", "pappa"));
66          assertEquals(1, distance.apply("papaa", "pappa"));
67          assertEquals(3, distance.apply("karolin", "kathrin"));
68          assertEquals(3, distance.apply("karolin", "kerstin"));
69          assertEquals(2, distance.apply("1011101", "1001001"));
70          assertEquals(3, distance.apply("2173896", "2233796"));
71          assertEquals(2, distance.apply("ATCG", "ACCC"));
72      }
73  
74  }