1 /*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "dictionary/utils/bloom_filter.h"
18
19 #include <gtest/gtest.h>
20
21 #include <algorithm>
22 #include <cstdlib>
23 #include <functional>
24 #include <random>
25 #include <unordered_set>
26 #include <vector>
27
28 namespace latinime {
29 namespace {
30
TEST(BloomFilterTest,TestFilter)31 TEST(BloomFilterTest, TestFilter) {
32 static const int TEST_RANDOM_DATA_MAX = 65536;
33 static const int ELEMENT_COUNT = 1000;
34 std::vector<int> elements;
35
36 // Initialize data set with random integers.
37 {
38 // Use the uniform integer distribution [0, TEST_RANDOM_DATA_MAX].
39 std::uniform_int_distribution<int> distribution(0, TEST_RANDOM_DATA_MAX);
40 auto randomNumberGenerator = std::bind(distribution, std::mt19937());
41 for (int i = 0; i < ELEMENT_COUNT; ++i) {
42 elements.push_back(randomNumberGenerator());
43 }
44 }
45
46 // Make sure BloomFilter contains nothing by default.
47 BloomFilter bloomFilter;
48 for (const int elem : elements) {
49 ASSERT_FALSE(bloomFilter.isInFilter(elem));
50 }
51
52 // Copy some of the test vector into bloom filter.
53 std::unordered_set<int> elementsThatHaveBeenSetInFilter;
54 {
55 // Use the uniform integer distribution [0, 1].
56 std::uniform_int_distribution<int> distribution(0, 1);
57 auto randomBitGenerator = std::bind(distribution, std::mt19937());
58 for (const int elem : elements) {
59 if (randomBitGenerator() == 0) {
60 bloomFilter.setInFilter(elem);
61 elementsThatHaveBeenSetInFilter.insert(elem);
62 }
63 }
64 }
65
66 for (const int elem : elements) {
67 const bool existsInFilter = bloomFilter.isInFilter(elem);
68 const bool hasBeenSetInFilter =
69 elementsThatHaveBeenSetInFilter.find(elem) != elementsThatHaveBeenSetInFilter.end();
70 if (hasBeenSetInFilter) {
71 EXPECT_TRUE(existsInFilter) << "elem: " << elem;
72 }
73 if (!existsInFilter) {
74 EXPECT_FALSE(hasBeenSetInFilter) << "elem: " << elem;
75 }
76 }
77 }
78
79 } // namespace
80 } // namespace latinime
81