Package com.yahoo.compress

Class Compressor

java.lang.Object
com.yahoo.compress.Compressor
public class Compressor extends Object
Compressor which can compress and decompress in various formats. This class is thread safe. Creating a reusable instance is faster than creating instances as needed.
Author:
bratseth

  • Constructor Details

    • Compressor

      public Compressor()
      Creates a compressor with default settings.

    • Compressor

      public Compressor(CompressionType type)
      Creates a compressor with a default compression type.

    • Compressor

      public Compressor(CompressionType type, int level)

    • Compressor

      public Compressor(CompressionType type, int level, double compressionThresholdFactor, int compressMinSizeBytes)
      Creates a compressor.
      Parameters:
      type - the type of compression to use to compress data
      level - a number between 0 and 9 where a higher value means more compression
      compressionThresholdFactor - the compression factor we need to achieve to return the compressed data instead of raw data
      compressMinSizeBytes - the minimal input data size to perform compression

  • Method Details

    • type

      public CompressionType type()
      Returns the default compression type used by this

    • level

      public int level()
      Returns the compression level this will use - a number between 0 and 9 where higher means more compression

    • compressionThresholdFactor

      public double compressionThresholdFactor()
      Returns the compression factor we need to achieve to return compressed rather than raw data

    • compressMinSizeBytes

      public int compressMinSizeBytes()
      Returns the minimal data size required to perform compression

    • compress

      public Compressor.Compression compress(CompressionType requestedCompression, byte[] data, Optional<Integer> uncompressedSize)
      Compresses some data
      Parameters:
      requestedCompression - the desired compression type, which will be used if the data is deemed suitable. Not all the existing types are actually supported.
      data - the data to compress. This array is only read by this method.
      uncompressedSize - uncompressedSize the size in bytes of the data array. If this is not present, it is assumed that the size is the same as the data array size, i.e that it is completely filled with uncompressed data.
      Returns:
      the compression result
      Throws:
      IllegalArgumentException - if the compression type is not supported

    • compress

      public Compressor.Compression compress(CompressionType requestedCompression, byte[] data, int offset, int len)

    • compress

      public Compressor.Compression compress(CompressionType requestedCompression, byte[] data)
      Compresses some data using the requested compression type

    • compress

      public Compressor.Compression compress(byte[] data, int uncompressedSize)
      Compresses some data using the compression type of this compressor

    • compress

      public Compressor.Compression compress(byte[] data)
      Compresses some data using the compression type of this compressor

    • decompress

      public byte[] decompress(CompressionType compression, byte[] compressedData, int compressedDataOffset, int expectedUncompressedSize, Optional<Integer> expectedCompressedSize)
      Decompresses some data
      Parameters:
      compression - the compression type used
      compressedData - the compressed data. This array is only read by this method.
      compressedDataOffset - the offset in the compressed data at which to start decompression
      expectedUncompressedSize - the uncompressed size in bytes of this data
      expectedCompressedSize - the expected compressed size of the data in bytes, optionally for validation with LZ4.
      Returns:
      the uncompressed data, of the given size
      Throws:
      IllegalArgumentException - if the compression type is not supported
      IllegalStateException - if the expected compressed size is non-empty and specifies a different size than the actual size

    • decompress

      public byte[] decompress(byte[] compressedData, CompressionType compressionType, int uncompressedSize)
      Decompresses some data

    • decompress

      public byte[] decompress(Compressor.Compression compression)
      Decompresses some data

    • compressUnconditionally

      public byte[] compressUnconditionally(byte[] input)

    • compressUnconditionally

      public byte[] compressUnconditionally(ByteBuffer input)

    • decompressUnconditionally

      public void decompressUnconditionally(ByteBuffer input, ByteBuffer output)

    • decompressUnconditionally

      public byte[] decompressUnconditionally(byte[] input, int srcOffset, int uncompressedLen)

    • warmup

      public long warmup(double seconds)