1 package org.eclipse.aether.spi.connector.checksum;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.nio.ByteBuffer;
23
24 /**
25 * Implementation performing checksum calculation for specific algorithm. Instances of this interface are stateful,
26 * non-thread safe, and should not be reused.
27 *
28 * @since 1.8.0
29 */
30 public interface ChecksumAlgorithm
31 {
32 /**
33 * Updates the checksum algorithm inner state with input.
34 */
35 void update( ByteBuffer input );
36
37 /**
38 * Returns the algorithm end result as string, never {@code null}. After invoking this method, this instance should
39 * be discarded and not reused. For new checksum calculation you have to get new instance.
40 *
41 * Values returned by this method are handled as "opaque strings", and are used for simple equality checks (matches
42 * or not matches the checksum), and are also persisted in this form (locally to file system but also uploaded as
43 * checksum files). Resolver itself never tries to "decode" or "interpret" this string in any other way.
44 */
45 String checksum();
46 }