org.apache.hadoop.hbase.io.compress

Enum Compression.Algorithm

java.lang.Object

java.lang.Enum<Compression.Algorithm>

org.apache.hadoop.hbase.io.compress.Compression.Algorithm

All Implemented Interfaces:

Serializable, Comparable<Compression.Algorithm>

Enclosing class:

Compression

@InterfaceAudience.Public
public static enum Compression.Algorithm
extends Enum<Compression.Algorithm>

Compression algorithms. The ordinal of these cannot change or else you risk breaking all existing HFiles out there. Even the ones that are not compressed! (They use the NONE algorithm)

Enum Constant Summary

Enum Constants

Enum Constant and Description
BROTLI
BZIP2
GZ
LZ4
LZMA
LZO
NONE
SNAPPY
ZSTD

Method Summary

Modifier and Type	Method and Description
OutputStream	createCompressionStream(OutputStream downStream, org.apache.hadoop.io.compress.Compressor compressor, int downStreamBufferSize)
InputStream	createDecompressionStream(InputStream downStream, org.apache.hadoop.io.compress.Decompressor decompressor, int downStreamBufferSize)
org.apache.hadoop.io.compress.CompressionOutputStream	createPlainCompressionStream(OutputStream downStream, org.apache.hadoop.io.compress.Compressor compressor) Creates a compression stream without any additional wrapping into buffering streams.
ByteBuffDecompressor	getByteBuffDecompressor() Be sure to call supportsByteBuffDecompression() before calling this method.
org.apache.hadoop.io.compress.Compressor	getCompressor()
org.apache.hadoop.io.compress.Decompressor	getDecompressor()
Compression.HFileDecompressionContext	getHFileDecompressionContextForConfiguration(org.apache.hadoop.conf.Configuration conf) Get an object that holds settings used by ByteBuffDecompressor.
String	getName()
abstract org.apache.hadoop.io.compress.CompressionCodec	reload(org.apache.hadoop.conf.Configuration conf) Reload configuration for the given algorithm.
void	returnByteBuffDecompressor(ByteBuffDecompressor decompressor)
void	returnCompressor(org.apache.hadoop.io.compress.Compressor compressor)
void	returnDecompressor(org.apache.hadoop.io.compress.Decompressor decompressor)
boolean	supportsByteBuffDecompression() Signals if this codec theoretically supports decompression on ByteBuffs.
static Compression.Algorithm	valueOf(String name) Returns the enum constant of this type with the specified name.
static Compression.Algorithm[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

LZO

public static final Compression.Algorithm LZO

GZ

public static final Compression.Algorithm GZ

NONE

public static final Compression.Algorithm NONE

SNAPPY

public static final Compression.Algorithm SNAPPY

LZ4

public static final Compression.Algorithm LZ4

BZIP2

public static final Compression.Algorithm BZIP2

ZSTD

public static final Compression.Algorithm ZSTD

LZMA

public static final Compression.Algorithm LZMA

BROTLI

public static final Compression.Algorithm BROTLI

Method Detail

values

public static Compression.Algorithm[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (Compression.Algorithm c : Compression.Algorithm.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static Compression.Algorithm valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

reload

public abstract org.apache.hadoop.io.compress.CompressionCodec reload(org.apache.hadoop.conf.Configuration conf)

Reload configuration for the given algorithm.

NOTE: Experts only. This can only be done safely during process startup, before the algorithm's codecs are in use. If the codec implementation is changed, the new implementation may not be fully compatible with what was loaded at static initialization time, leading to potential data corruption. Mostly used by unit tests.

Parameters:

conf - configuration

createDecompressionStream

public InputStream createDecompressionStream(InputStream downStream,
                                             org.apache.hadoop.io.compress.Decompressor decompressor,
                                             int downStreamBufferSize)
                                      throws IOException

Throws:

IOException

createCompressionStream

public OutputStream createCompressionStream(OutputStream downStream,
                                            org.apache.hadoop.io.compress.Compressor compressor,
                                            int downStreamBufferSize)
                                     throws IOException

Throws:

IOException

createPlainCompressionStream

public org.apache.hadoop.io.compress.CompressionOutputStream createPlainCompressionStream(OutputStream downStream,
                                                                                          org.apache.hadoop.io.compress.Compressor compressor)
                                                                                   throws IOException

Creates a compression stream without any additional wrapping into buffering streams.

Throws:

IOException

getCompressor

public org.apache.hadoop.io.compress.Compressor getCompressor()

returnCompressor

public void returnCompressor(org.apache.hadoop.io.compress.Compressor compressor)

getDecompressor

public org.apache.hadoop.io.compress.Decompressor getDecompressor()

returnDecompressor

public void returnDecompressor(org.apache.hadoop.io.compress.Decompressor decompressor)

supportsByteBuffDecompression

public boolean supportsByteBuffDecompression()

Signals if this codec theoretically supports decompression on ByteBuffs. This can be faster than using a DecompressionStream. If this method returns true, you can call getByteBuffDecompressor() to obtain a ByteBuffDecompressor. You must then also call ByteBuffDecompressor.canDecompress(ByteBuff, ByteBuff) before attempting decompression, to verify if that decompressor is capable of handling your particular input and output buffers.

getByteBuffDecompressor

public ByteBuffDecompressor getByteBuffDecompressor()

Be sure to call supportsByteBuffDecompression() before calling this method.

Throws:

IllegalStateException - if the codec does not support block decompression

returnByteBuffDecompressor

public void returnByteBuffDecompressor(ByteBuffDecompressor decompressor)

getHFileDecompressionContextForConfiguration

@Nullable
public Compression.HFileDecompressionContext getHFileDecompressionContextForConfiguration(org.apache.hadoop.conf.Configuration conf)

Get an object that holds settings used by ByteBuffDecompressor. It's expensive to pull these from a Configuration object every time we decompress a block, so pull them here when, for example, opening an HFile, and reuse the returned HFileDecompressionContext as much as possible. The concrete class of this object will be one that is specific to the codec implementation in use. You don't need to inspect it yourself, just pass it along to ByteBuffDecompressor#reinit(HFileDecompressionContext).

getName

public String getName()