View Javadoc
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  }