org.apache.flink.runtime.io.compression

Interface BlockCompressor

All Known Implementing Classes:

AirBlockCompressor, Lz4BlockCompressor

public interface BlockCompressor

A compressor which compresses a whole byte array each time. It will read from and write to byte arrays given from the outside, reducing copy time.

Method Summary

Modifier and Type	Method and Description
int	compress(byte[] src, int srcOff, int srcLen, byte[] dst, int dstOff) Compress data read from src, and write the compressed data to dst.
int	compress(ByteBuffer src, int srcOff, int srcLen, ByteBuffer dst, int dstOff) Compress source data read from (Buffer.position() + srcOff), and write the compressed data to dst.
int	getMaxCompressedSize(int srcSize) Get the max compressed size for a given original size.

Method Detail

getMaxCompressedSize

int getMaxCompressedSize(int srcSize)

Get the max compressed size for a given original size.

compress

int compress(ByteBuffer src,
             int srcOff,
             int srcLen,
             ByteBuffer dst,
             int dstOff)
      throws BufferCompressionException

Compress source data read from (Buffer.position() + srcOff), and write the compressed data to dst.

Parameters:

src - Uncompressed data to read from

srcOff - The start offset of uncompressed data

srcLen - The length of data which want to be compressed

dst - The target to write compressed data

dstOff - The start offset to write the compressed data

Returns:

Length of compressed data

Throws:

BufferCompressionException - if exception thrown when compressing

compress

int compress(byte[] src,
             int srcOff,
             int srcLen,
             byte[] dst,
             int dstOff)
      throws BufferCompressionException

Compress data read from src, and write the compressed data to dst.

Parameters:

src - Uncompressed data to read from

srcOff - The start offset of uncompressed data

srcLen - The length of data which want to be compressed

dst - The target to write compressed data

dstOff - The start offset to write the compressed data

Returns:

Length of compressed data

Throws:

BufferCompressionException - if exception thrown when compressing