Package org.apache.beam.sdk.io

Enum Compression

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Comparable<Compression>
    public enum Compression
extends java.lang.Enum<Compression>
    Various compression types for reading/writing files.

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description
      AUTO
      When reading a file, automatically determine the compression type based on filename extension.
      BZIP2
      BZip compression.
      DEFLATE
      Deflate compression.
      GZIP
      GZip compression.
      LZO
      LZO compression using LZO codec.
      LZOP
      LZOP compression using LZOP codec.
      SNAPPY
      Google Snappy compression.
      UNCOMPRESSED
      No compression.
      ZIP
      Zip compression.
      ZSTD
      ZStandard compression.

    • Method Summary

      All Methods Static Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      static Compression detect​(java.lang.String filename)  
      java.lang.String getSuggestedSuffix()  
      boolean isCompressed​(java.lang.String filename)  
      boolean matches​(java.lang.String filename)  
      abstract java.nio.channels.ReadableByteChannel readDecompressed​(java.nio.channels.ReadableByteChannel channel)  
      static Compression valueOf​(java.lang.String name)
      Returns the enum constant of this type with the specified name.
      static Compression[] values()
      Returns an array containing the constants of this enum type, in the order they are declared.
      abstract java.nio.channels.WritableByteChannel writeCompressed​(java.nio.channels.WritableByteChannel channel)  

      • 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

      • AUTO

        public static final Compression AUTO
        When reading a file, automatically determine the compression type based on filename extension. Not applicable when writing files.

      • UNCOMPRESSED

        public static final Compression UNCOMPRESSED
        No compression.

      • GZIP

        public static final Compression GZIP
        GZip compression.

      • BZIP2

        public static final Compression BZIP2
        BZip compression.

      • ZIP

        public static final Compression ZIP
        Zip compression.

      • ZSTD

        public static final Compression ZSTD
        ZStandard compression.

        The .zst extension is specified in RFC 8478.

        The Beam Java SDK does not pull in the Zstd library by default, so it is the user's responsibility to declare an explicit dependency on zstd-jni. Attempts to read or write .zst files without zstd-jni loaded will result in NoClassDefFoundError at runtime.

      • LZO

        public static final Compression LZO
        LZO compression using LZO codec. .lzo_deflate extension is specified for files which use the LZO algorithm without headers.

        The Beam Java SDK does not pull in the required libraries for LZO compression by default, so it is the user's responsibility to declare an explicit dependency on io.airlift:aircompressor and com.facebook.presto.hadoop:hadoop-apache2. Attempts to read or write .lzo_deflate files without io.airlift:aircompressor and com.facebook.presto.hadoop:hadoop-apache2 loaded will result in a NoClassDefFoundError at runtime.

      • LZOP

        public static final Compression LZOP
        LZOP compression using LZOP codec. .lzo extension is specified for files with magic bytes and headers.

        Warning: The LZOP codec being used does not support concatenated LZOP streams and will silently ignore data after the end of the first LZOP stream.

        The Beam Java SDK does not pull in the required libraries for LZOP compression by default, so it is the user's responsibility to declare an explicit dependency on io.airlift:aircompressor and com.facebook.presto.hadoop:hadoop-apache2. Attempts to read or write .lzo files without io.airlift:aircompressor and com.facebook.presto.hadoop:hadoop-apache2 loaded will result in a NoClassDefFoundError at runtime.

      • DEFLATE

        public static final Compression DEFLATE
        Deflate compression.

      • SNAPPY

        public static final Compression SNAPPY
        Google Snappy compression.

    • Method Detail

      • values

        public static Compression[] 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 c : Compression.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 valueOf​(java.lang.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:
        java.lang.IllegalArgumentException - if this enum type has no constant with the specified name
        java.lang.NullPointerException - if the argument is null

      • getSuggestedSuffix

        public java.lang.String getSuggestedSuffix()

      • matches

        public boolean matches​(java.lang.String filename)

      • isCompressed

        public boolean isCompressed​(java.lang.String filename)

      • detect

        public static Compression detect​(java.lang.String filename)

      • readDecompressed

        public abstract java.nio.channels.ReadableByteChannel readDecompressed​(java.nio.channels.ReadableByteChannel channel)
                                                                throws java.io.IOException
        Throws:
        java.io.IOException

      • writeCompressed

        public abstract java.nio.channels.WritableByteChannel writeCompressed​(java.nio.channels.WritableByteChannel channel)
                                                               throws java.io.IOException
        Throws:
        java.io.IOException