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.codec.digest;
18
19 import static org.junit.jupiter.api.Assertions.assertEquals;
20
21 import java.util.Arrays;
22
23 import org.junit.jupiter.api.Test;
24
25 /**
26 * Test class for PureJavaCrc32C. Test data was derived from https://tools.ietf.org/html/rfc3720#appendix-B.4
27 */
28 public class PureJavaCrc32CTest {
29
30 private final PureJavaCrc32C crc = new PureJavaCrc32C();
31
32 private final byte[] data = new byte[32];
33
34 // Using int because only want 32 bits
35 private void check(final int expected) {
36 crc.reset();
37 crc.update(data, 0, data.length);
38 final int actual = (int) crc.getValue();
39 assertEquals(Integer.toHexString(expected), Integer.toHexString(actual));
40 }
41
42 @Test
43 public void testDecreasing() {
44 for (int i = 0; i < data.length; i++) {
45 data[i] = (byte) (31 - i);
46 }
47 check(0x113fdb5c); // 5c db 3f 11
48 }
49
50 @Test
51 public void testIncreasing() {
52 for (int i = 0; i < data.length; i++) {
53 data[i] = (byte) i;
54 }
55 check(0x46dd794e); // 4e 79 dd 46
56 }
57
58 @Test
59 public void testOnes() {
60 Arrays.fill(data, (byte) 0xFF);
61 check(0x62a8ab43); // 43 ab a8 62
62 }
63
64 @Test
65 public void testZeros() {
66 Arrays.fill(data, (byte) 0);
67 check(0x8a9136aa); // aa 36 91 8a
68 }
69
70 }