1 /*
2 * GordianKnot: Security Suite
3 * Copyright 2012-2026. Tony Washer
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
6 * use this file except in compliance with the License. You may obtain a copy
7 * 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, WITHOUT
13 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
14 * License for the specific language governing permissions and limitations under
15 * the License.
16 */
17 package io.github.tonywasher.joceanus.gordianknot.api.digest;
18
19 import io.github.tonywasher.joceanus.gordianknot.api.base.GordianConsumer;
20 import io.github.tonywasher.joceanus.gordianknot.api.base.GordianException;
21
22 /**
23 * GordianKnot interface for Message Digests.
24 */
25 public interface GordianDigest
26 extends GordianConsumer {
27 /**
28 * Obtain DigestSpec.
29 *
30 * @return the digestSpec
31 */
32 GordianDigestSpec getDigestSpec();
33
34 /**
35 * Obtain the digest size.
36 *
37 * @return the digest size
38 */
39 int getDigestSize();
40
41 /**
42 * Calculate the digest.
43 *
44 * @return the digest
45 */
46 byte[] finish();
47
48 /**
49 * Calculate the Digest, and return it in the buffer provided.
50 *
51 * @param pBuffer the buffer to return the digest in.
52 * @param pOffset the offset in the buffer to store the digest.
53 * @return the number of bytes placed into buffer
54 * @throws GordianException on error
55 */
56 int finish(byte[] pBuffer,
57 int pOffset) throws GordianException;
58
59 /**
60 * Update the digest, calculate and reset it.
61 *
62 * @param pBytes the bytes to update with.
63 * @return the digest
64 */
65 default byte[] finish(final byte[] pBytes) {
66 update(pBytes);
67 return finish();
68 }
69 }