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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements. See the NOTICE file distributed with this
4    * work for additional information regarding copyright ownership. The ASF
5    * licenses this file to you under the Apache License, Version 2.0 (the
6    * "License"); you may not use this file except in compliance with the License.
7    * 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, WITHOUT
13   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
14   * License for the specific language governing permissions and limitations
15   * under the License.
16   */
17  package org.apache.hadoop.hbase.io.encoding;
18  
19  import java.io.IOException;
20  
21  import org.apache.hadoop.classification.InterfaceAudience;
22  import org.apache.hadoop.hbase.io.hfile.BlockType;
23  import org.apache.hadoop.hbase.io.hfile.HFileContext;
24  
25  /**
26   * An encoding context that is created by a writer's encoder, and is shared
27   * across the writer's whole lifetime.
28   *
29   * @see HFileBlockDecodingContext for decoding
30   *
31   */
32  @InterfaceAudience.Private
33  public interface HFileBlockEncodingContext {
34  
35    /**
36     * @return the block type after encoding
37     */
38    BlockType getBlockType();
39  
40    /**
41     * @return the {@link DataBlockEncoding} encoding used
42     */
43    DataBlockEncoding getDataBlockEncoding();
44  
45    /**
46     * Do any action that needs to be performed after the encoding.
47     * Compression is also included if a non-null compression algorithm is used
48     *
49     * @param blockType
50     * @throws IOException
51     */
52    void postEncoding(BlockType blockType) throws IOException;
53  
54    /**
55     * Releases the resources used.
56     */
57    void close();
58  
59    /**
60     * @return HFile context information
61     */
62    HFileContext getHFileContext();
63  
64    /**
65     * Sets the encoding state.
66     * @param state
67     */
68    void setEncodingState(EncodingState state);
69  
70    /**
71     * @return the encoding state
72     */
73    EncodingState getEncodingState();
74  
75    /**
76     * @param uncompressedBytesWithHeader encoded bytes with header
77     * @return Bytes with header which are ready to write out to disk. This is compressed and
78     *         encrypted bytes applying the set compression algorithm and encryption.
79     */
80    byte[] compressAndEncrypt(byte[] uncompressedBytesWithHeader) throws IOException;
81  }