Package org.apache.parquet.format

Enum PageHeader._Fields

java.lang.Object

java.lang.Enum<PageHeader._Fields>

org.apache.parquet.format.PageHeader._Fields

All Implemented Interfaces:

Serializable, Comparable<PageHeader._Fields>, org.apache.thrift.TFieldIdEnum

Enclosing class:

PageHeader

public static enum PageHeader._Fields
extends Enum<PageHeader._Fields>
implements org.apache.thrift.TFieldIdEnum

The set of fields this struct contains, along with convenience methods for finding and manipulating them.

Enum Constant Summary

Enum Constants

Enum Constant	Description
COMPRESSED_PAGE_SIZE	Compressed (and potentially encrypted) page size in bytes, not including this header *
CRC	The 32bit CRC for the page, to be be calculated as follows: - Using the standard CRC32 algorithm - On the data only, i.e.
DATA_PAGE_HEADER
DATA_PAGE_HEADER_V2
DICTIONARY_PAGE_HEADER
INDEX_PAGE_HEADER
TYPE	the type of the page: indicates which of the *_header fields is set *
UNCOMPRESSED_PAGE_SIZE	Uncompressed page size in bytes (not including this header) *

Method Summary

Modifier and Type	Method	Description
static PageHeader._Fields	findByName(String name)	Find the _Fields constant that matches name, or null if its not found.
static PageHeader._Fields	findByThriftId(int fieldId)	Find the _Fields constant that matches fieldId, or null if its not found.
static PageHeader._Fields	findByThriftIdOrThrow(int fieldId)	Find the _Fields constant that matches fieldId, throwing an exception if it is not found.
String	getFieldName()
short	getThriftFieldId()
static PageHeader._Fields	valueOf(String name)	Returns the enum constant of this type with the specified name.
static PageHeader._Fields[]	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

TYPE

public static final PageHeader._Fields TYPE

the type of the page: indicates which of the *_header fields is set *

See Also:

PageType

UNCOMPRESSED_PAGE_SIZE

public static final PageHeader._Fields UNCOMPRESSED_PAGE_SIZE

Uncompressed page size in bytes (not including this header) *

COMPRESSED_PAGE_SIZE

public static final PageHeader._Fields COMPRESSED_PAGE_SIZE

Compressed (and potentially encrypted) page size in bytes, not including this header *

CRC

public static final PageHeader._Fields CRC

The 32bit CRC for the page, to be be calculated as follows: - Using the standard CRC32 algorithm - On the data only, i.e. this header should not be included. 'Data' hereby refers to the concatenation of the repetition levels, the definition levels and the column value, in this exact order. - On the encoded versions of the repetition levels, definition levels and column values - On the compressed versions of the repetition levels, definition levels and column values where possible; - For v1 data pages, the repetition levels, definition levels and column values are always compressed together. If a compression scheme is specified, the CRC shall be calculated on the compressed version of this concatenation. If no compression scheme is specified, the CRC shall be calculated on the uncompressed version of this concatenation. - For v2 data pages, the repetition levels and definition levels are handled separately from the data and are never compressed (only encoded). If a compression scheme is specified, the CRC shall be calculated on the concatenation of the uncompressed repetition levels, uncompressed definition levels and the compressed column values. If no compression scheme is specified, the CRC shall be calculated on the uncompressed concatenation. If enabled, this allows for disabling checksumming in HDFS if only a few pages need to be read.

DATA_PAGE_HEADER

public static final PageHeader._Fields DATA_PAGE_HEADER

INDEX_PAGE_HEADER

public static final PageHeader._Fields INDEX_PAGE_HEADER

DICTIONARY_PAGE_HEADER

public static final PageHeader._Fields DICTIONARY_PAGE_HEADER

DATA_PAGE_HEADER_V2

public static final PageHeader._Fields DATA_PAGE_HEADER_V2

Method Detail

values

public static PageHeader._Fields[] 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 (PageHeader._Fields c : PageHeader._Fields.values())
    System.out.println(c);

Returns:

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

valueOf

public static PageHeader._Fields 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

findByThriftId

public static PageHeader._Fields findByThriftId(int fieldId)

Find the _Fields constant that matches fieldId, or null if its not found.

findByThriftIdOrThrow

public static PageHeader._Fields findByThriftIdOrThrow(int fieldId)

Find the _Fields constant that matches fieldId, throwing an exception if it is not found.

findByName

public static PageHeader._Fields findByName(String name)

Find the _Fields constant that matches name, or null if its not found.

getThriftFieldId

public short getThriftFieldId()

Specified by:

getThriftFieldId in interface org.apache.thrift.TFieldIdEnum

getFieldName

public String getFieldName()

Specified by:

getFieldName in interface org.apache.thrift.TFieldIdEnum