Package edu.stanford.slac.archiverappliance.plain.parquet

Class ParquetInfo

java.lang.Object

edu.stanford.slac.archiverappliance.plain.FileInfo

edu.stanford.slac.archiverappliance.plain.parquet.ParquetInfo

public class ParquetInfo
extends FileInfo

An implementation of FileInfo for Parquet files.

This class is responsible for reading and interpreting the metadata and data within a single Parquet file. It provides methods to access file-level information such as the PV name, data year, and data type. It also offers wrappers methods for retrieving specific events, such as the first, last, or an event at a particular time, by leveraging Parquet's internal metadata (like column statistics) and predicate pushdown filters.

See Also:

• ParquetPlainFileHandler
• FileInfo

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ParquetInfo.ColumnName
static enum	ParquetInfo.MetaDataKey

Field Summary

Fields inherited from class edu.stanford.slac.archiverappliance.plain.FileInfo

firstEvent, lastEvent

Constructor Summary

Constructors

Constructor	Description
ParquetInfo(Path pvPath)
ParquetInfo(Path pvPath, org.apache.parquet.ParquetReadOptions readOptions)

Method Summary

Modifier and Type	Method	Description
static ParquetInfo	fetchFileInfo(Path path)	Create the fileinfo for a given path
org.apache.parquet.hadoop.metadata.CompressionCodecName	getCompressionCodecName()	Gets the compression codec used for the file.
short	getDataYear()
DBRTimeEvent	getFirstEvent()
DBRTimeEvent	getLastEvent()
String	getPVName()
ArchDBRTypes	getType()
String	toString()

Methods inherited from class edu.stanford.slac.archiverappliance.plain.FileInfo

getFirstEventInstant, getLastEventInstant

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

ParquetInfo

public ParquetInfo(Path pvPath,
 org.apache.parquet.ParquetReadOptions readOptions)
            throws IOException

Throws:

IOException

ParquetInfo

public ParquetInfo(Path pvPath)
            throws IOException

Throws:

IOException

Method Details

fetchFileInfo

public static ParquetInfo fetchFileInfo(Path path)

Create the fileinfo for a given path

Parameters:

path - Path to file

Returns:

ParquetInfo

toString

public String toString()

Overrides:

toString in class FileInfo

getPVName

public String getPVName()

Specified by:

getPVName in class FileInfo

getDataYear

public short getDataYear()

Specified by:

getDataYear in class FileInfo

getType

public ArchDBRTypes getType()

Specified by:

getType in class FileInfo

getFirstEvent

public DBRTimeEvent getFirstEvent()

Specified by:

getFirstEvent in class FileInfo

getLastEvent

public DBRTimeEvent getLastEvent()

Specified by:

getLastEvent in class FileInfo

getCompressionCodecName

public org.apache.parquet.hadoop.metadata.CompressionCodecName getCompressionCodecName()

Gets the compression codec used for the file.

Returns:

The CompressionCodecName used.