org.apache.parquet.format.Encoding Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of hive-apache Show documentation
Shaded version of Apache Hive for Trino
There is a newer version: 3.1.2-23
/**
 * Autogenerated by Thrift Compiler (0.13.0)
 *
 * DO NOT EDIT UNLESS YOU ARE SURE THAT YOU KNOW WHAT YOU ARE DOING
 *  @generated
 */
package org.apache.parquet.format;


/**
 * Encodings supported by Parquet.  Not all encodings are valid for all types.  These
 * enums are also used to specify the encoding of definition and repetition levels.
 * See the accompanying doc for the details of the more complicated encodings.
 */
@javax.annotation.Generated(value = "Autogenerated by Thrift Compiler (0.13.0)", date = "2021-03-17")
public enum Encoding implements org.apache.thrift.TEnum {
  /**
   * Default encoding.
   * BOOLEAN - 1 bit per value. 0 is false; 1 is true.
   * INT32 - 4 bytes per value.  Stored as little-endian.
   * INT64 - 8 bytes per value.  Stored as little-endian.
   * FLOAT - 4 bytes per value.  IEEE. Stored as little-endian.
   * DOUBLE - 8 bytes per value.  IEEE. Stored as little-endian.
   * BYTE_ARRAY - 4 byte length stored as little endian, followed by bytes.
   * FIXED_LEN_BYTE_ARRAY - Just the bytes.
   */
  PLAIN(0),
  /**
   * Deprecated: Dictionary encoding. The values in the dictionary are encoded in the
   * plain type.
   * in a data page use RLE_DICTIONARY instead.
   * in a Dictionary page use PLAIN instead
   */
  PLAIN_DICTIONARY(2),
  /**
   * Group packed run length encoding. Usable for definition/repetition levels
   * encoding and Booleans (on one bit: 0 is false; 1 is true.)
   */
  RLE(3),
  /**
   * Bit packed encoding.  This can only be used if the data has a known max
   * width.  Usable for definition/repetition levels encoding.
   */
  BIT_PACKED(4),
  /**
   * Delta encoding for integers. This can be used for int columns and works best
   * on sorted data
   */
  DELTA_BINARY_PACKED(5),
  /**
   * Encoding for byte arrays to separate the length values and the data. The lengths
   * are encoded using DELTA_BINARY_PACKED
   */
  DELTA_LENGTH_BYTE_ARRAY(6),
  /**
   * Incremental-encoded byte array. Prefix lengths are encoded using DELTA_BINARY_PACKED.
   * Suffixes are stored as delta length byte arrays.
   */
  DELTA_BYTE_ARRAY(7),
  /**
   * Dictionary encoding: the ids are encoded using the RLE encoding
   */
  RLE_DICTIONARY(8),
  /**
   * Encoding for floating-point data.
   * K byte-streams are created where K is the size in bytes of the data type.
   * The individual bytes of an FP value are scattered to the corresponding stream and
   * the streams are concatenated.
   * This itself does not reduce the size of the data but can lead to better compression
   * afterwards.
   */
  BYTE_STREAM_SPLIT(9);

  private final int value;

  private Encoding(int value) {
    this.value = value;
  }

  /**
   * Get the integer value of this enum value, as defined in the Thrift IDL.
   */
  public int getValue() {
    return value;
  }

  /**
   * Find a the enum type by its integer value, as defined in the Thrift IDL.
   * @return null if the value is not found.
   */
  @org.apache.thrift.annotation.Nullable
  public static Encoding findByValue(int value) { 
    switch (value) {
      case 0:
        return PLAIN;
      case 2:
        return PLAIN_DICTIONARY;
      case 3:
        return RLE;
      case 4:
        return BIT_PACKED;
      case 5:
        return DELTA_BINARY_PACKED;
      case 6:
        return DELTA_LENGTH_BYTE_ARRAY;
      case 7:
        return DELTA_BYTE_ARRAY;
      case 8:
        return RLE_DICTIONARY;
      case 9:
        return BYTE_STREAM_SPLIT;
      default:
        return null;
    }
  }
}