org.apache.hudi.org.apache.hadoop.hbase.io.hfile.HFileDataBlockEncoder Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with this
* work for additional information regarding copyright ownership. The ASF
* licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package org.apache.hadoop.hbase.io.hfile;
import java.io.DataOutputStream;
import java.io.IOException;
import org.apache.yetus.audience.InterfaceAudience;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.io.encoding.DataBlockEncoding;
import org.apache.hadoop.hbase.io.encoding.HFileBlockDecodingContext;
import org.apache.hadoop.hbase.io.encoding.HFileBlockEncodingContext;
import org.apache.hadoop.hbase.util.Bytes;
/**
* Controls what kind of data block encoding is used. If data block encoding is
* not set or the given block is not a data block (encoded or not), methods
* should just return the unmodified block.
*/
@InterfaceAudience.Private
public interface HFileDataBlockEncoder {
/** Type of encoding used for data blocks in HFile. Stored in file info. */
byte[] DATA_BLOCK_ENCODING = Bytes.toBytes("DATA_BLOCK_ENCODING");
/**
* Starts encoding for a block of KeyValues. Call
* {@link #endBlockEncoding(HFileBlockEncodingContext, DataOutputStream, byte[], BlockType)}
* to finish encoding of a block.
* @param encodingCtx
* @param out
* @throws IOException
*/
void startBlockEncoding(HFileBlockEncodingContext encodingCtx, DataOutputStream out)
throws IOException;
/**
* Encodes a KeyValue.
* @param cell
* @param encodingCtx
* @param out
* @throws IOException
*/
void encode(Cell cell, HFileBlockEncodingContext encodingCtx, DataOutputStream out)
throws IOException;
/**
* Ends encoding for a block of KeyValues. Gives a chance for the encoder to do the finishing
* stuff for the encoded block. It must be called at the end of block encoding.
* @param encodingCtx
* @param out
* @param uncompressedBytesWithHeader
* @param blockType
* @throws IOException
*/
void endBlockEncoding(HFileBlockEncodingContext encodingCtx, DataOutputStream out,
byte[] uncompressedBytesWithHeader, BlockType blockType) throws IOException;
/**
* Decides whether we should use a scanner over encoded blocks.
* @return Whether to use encoded scanner.
*/
boolean useEncodedScanner();
/**
* Save metadata in HFile which will be written to disk
* @param writer writer for a given HFile
* @exception IOException on disk problems
*/
void saveMetadata(HFile.Writer writer)
throws IOException;
/** @return the data block encoding */
DataBlockEncoding getDataBlockEncoding();
/**
* @return the effective in-cache data block encoding, taking into account
* whether we are doing a compaction.
*/
public DataBlockEncoding getEffectiveEncodingInCache(boolean isCompaction);
/**
* Create an encoder specific encoding context object for writing. And the
* encoding context should also perform compression if compressionAlgorithm is
* valid.
*
* @param headerBytes header bytes
* @param fileContext HFile meta data
* @return a new {@link HFileBlockEncodingContext} object
*/
HFileBlockEncodingContext newDataBlockEncodingContext(byte[] headerBytes,
HFileContext fileContext);
/**
* create a encoder specific decoding context for reading. And the
* decoding context should also do decompression if compressionAlgorithm
* is valid.
*
* @param fileContext - HFile meta data
* @return a new {@link HFileBlockDecodingContext} object
*/
HFileBlockDecodingContext newDataBlockDecodingContext(HFileContext fileContext);
}