io.delta.kernel.internal.util

Class FileNames

java.lang.Object

io.delta.kernel.internal.util.FileNames

public final class FileNames
extends java.lang.Object

Method Summary

Modifier and Type	Method and Description
static Path	checkpointFileSingular(Path path, long version) Returns the path for a singular checkpoint up to the given version.
static java.util.List<Path>	checkpointFileWithParts(Path path, long version, int numParts) Returns the paths for all parts of the checkpoint up to the given version.
static long	checkpointVersion(Path path) Returns the version for the given checkpoint path.
static java.lang.String	deltaFile(Path path, long version) Returns the delta (json format) path for a given delta file.
static long	deltaVersion(Path path) Returns the version for the given delta path.
static long	getFileVersion(Path path) Get the version of the checkpoint, checksum or delta file.
static boolean	isCheckpointFile(java.lang.String fileName)
static boolean	isCommitFile(java.lang.String fileName)
static java.lang.String	listingPrefix(Path path, long version) Returns the prefix of all delta log files for the given version.

Methods inherited from class java.lang.Object

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

Method Detail

deltaFile

public static java.lang.String deltaFile(Path path,
                                         long version)

Returns the delta (json format) path for a given delta file.

deltaVersion

public static long deltaVersion(Path path)

Returns the version for the given delta path.

checkpointVersion

public static long checkpointVersion(Path path)

Returns the version for the given checkpoint path.

listingPrefix

public static java.lang.String listingPrefix(Path path,
                                             long version)

Returns the prefix of all delta log files for the given version.

Intended for use with listFrom to get all files from this version onwards. The returned Path will not exist as a file.

checkpointFileSingular

public static Path checkpointFileSingular(Path path,
                                          long version)

Returns the path for a singular checkpoint up to the given version.

In a future protocol version this path will stop being written.

checkpointFileWithParts

public static java.util.List<Path> checkpointFileWithParts(Path path,
                                                           long version,
                                                           int numParts)

Returns the paths for all parts of the checkpoint up to the given version.

In a future protocol version we will write this path instead of checkpointFileSingular.

Example of the format: 00000000000000004915.checkpoint.0000000020.0000000060.parquet is checkpoint part 20 out of 60 for the snapshot at version 4915. Zero padding is for lexicographic sorting.

isCheckpointFile

public static boolean isCheckpointFile(java.lang.String fileName)

isCommitFile

public static boolean isCommitFile(java.lang.String fileName)

getFileVersion

public static long getFileVersion(Path path)

Get the version of the checkpoint, checksum or delta file. Throws an error if an unexpected file type is seen. These unexpected files should be filtered out to ensure forward compatibility in cases where new file types are added, but without an explicit protocol upgrade.