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 * http://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.numbers.primes;
18
19 import java.util.Arrays;
20 import java.util.List;
21 import org.junit.jupiter.api.Assertions;
22 import org.junit.jupiter.api.Test;
23
24 /**
25 * Tests for examples contained in the user guide.
26 */
27 class UserGuideTest {
28
29 @Test
30 void testPrimes1() {
31 int n = 51237173;
32 boolean prime = Primes.isPrime(n);
33 int m = Primes.nextPrime(n);
34 Assertions.assertFalse(prime);
35 Assertions.assertEquals(51237233, m);
36
37 List<Integer> f1 = Primes.primeFactors(n);
38 List<Integer> f2 = Primes.primeFactors(m);
39 Assertions.assertEquals(Arrays.asList(13, 863, 4567), f1);
40 Assertions.assertEquals(Arrays.asList(m), f2);
41 // n == 13 * 863 * 4567
42 Assertions.assertEquals(n, f1.stream().mapToInt(i -> i).reduce((i, j) -> i * j).getAsInt());
43 }
44 }