1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.eclipse.aether.spi.connector.checksum;
20
21 import java.io.BufferedInputStream;
22 import java.io.ByteArrayInputStream;
23 import java.io.File;
24 import java.io.IOException;
25 import java.io.InputStream;
26 import java.nio.ByteBuffer;
27 import java.nio.file.Files;
28 import java.nio.file.Path;
29 import java.util.LinkedHashMap;
30 import java.util.List;
31 import java.util.Map;
32
33 /**
34 * Helper for checksum operations.
35 *
36 * @since 1.8.0
37 */
38 public final class ChecksumAlgorithmHelper {
39 private ChecksumAlgorithmHelper() {
40 // nop
41 }
42
43 /**
44 * Calculates checksums for specified data.
45 *
46 * @param data The content for which to calculate checksums, must not be {@code null}.
47 * @param factories The checksum algorithm factories to use, must not be {@code null}.
48 * @return The calculated checksums, indexed by algorithm name, or the exception that occurred while trying to
49 * calculate it, never {@code null}.
50 * @throws IOException In case of any problem.
51 */
52 public static Map<String, String> calculate(byte[] data, List<ChecksumAlgorithmFactory> factories)
53 throws IOException {
54 try (InputStream inputStream = new ByteArrayInputStream(data)) {
55 return calculate(inputStream, factories);
56 }
57 }
58
59 /**
60 * Calculates checksums for specified file.
61 *
62 * @param file The file for which to calculate checksums, must not be {@code null}.
63 * @param factories The checksum algorithm factories to use, must not be {@code null}.
64 * @return The calculated checksums, indexed by algorithm name, or the exception that occurred while trying to
65 * calculate it, never {@code null}.
66 * @throws IOException In case of any problem.
67 */
68 public static Map<String, String> calculate(File file, List<ChecksumAlgorithmFactory> factories)
69 throws IOException {
70 return calculate(file.toPath(), factories);
71 }
72
73 /**
74 * Calculates checksums for specified file.
75 *
76 * @param path The file for which to calculate checksums, must not be {@code null}.
77 * @param factories The checksum algorithm factories to use, must not be {@code null}.
78 * @return The calculated checksums, indexed by algorithm name, or the exception that occurred while trying to
79 * calculate it, never {@code null}.
80 * @throws IOException In case of any problem.
81 * @since 2.0.0
82 */
83 public static Map<String, String> calculate(Path path, List<ChecksumAlgorithmFactory> factories)
84 throws IOException {
85 try (InputStream inputStream = new BufferedInputStream(Files.newInputStream(path))) {
86 return calculate(inputStream, factories);
87 }
88 }
89
90 private static Map<String, String> calculate(InputStream inputStream, List<ChecksumAlgorithmFactory> factories)
91 throws IOException {
92 LinkedHashMap<String, ChecksumAlgorithm> algorithms = new LinkedHashMap<>();
93 factories.forEach(f -> algorithms.put(f.getName(), f.getAlgorithm()));
94 final byte[] buffer = new byte[1024 * 32];
95 for (; ; ) {
96 int read = inputStream.read(buffer);
97 if (read < 0) {
98 break;
99 }
100 for (ChecksumAlgorithm checksumAlgorithm : algorithms.values()) {
101 checksumAlgorithm.update(ByteBuffer.wrap(buffer, 0, read));
102 }
103 }
104 LinkedHashMap<String, String> result = new LinkedHashMap<>();
105 algorithms.forEach((k, v) -> result.put(k, v.checksum()));
106 return result;
107 }
108 }