Package io.delta.kernel.internal.checkpoints

Class Checkpointer

Object

io.delta.kernel.internal.checkpoints.Checkpointer

public class Checkpointer
extends Object

Class to load and write the CheckpointMetaData from `_last_checkpoint` file.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	LAST_CHECKPOINT_FILE_NAME	The name of the last checkpoint file

Constructor Summary

Constructors

Constructor	Description
Checkpointer(Path logPath)

Method Summary

Modifier and Type	Method	Description
static void	checkpoint(Engine engine, Clock clock, SnapshotImpl snapshot)
static Optional<CheckpointInstance>	findLastCompleteCheckpointBefore(Engine engine, Path tableLogPath, long version)	Find the last complete checkpoint before (strictly less than) a given version.
static Tuple2<Optional<CheckpointInstance>,Long>	findLastCompleteCheckpointBeforeHelper(Engine engine, Path tableLogPath, long version)	Helper method for `findLastCompleteCheckpointBefore` which also return the number of files searched.
static Optional<CheckpointInstance>	getLatestCompleteCheckpointFromList(List<CheckpointInstance> instances, CheckpointInstance notLaterThan)	Given a list of checkpoint files, pick the latest complete checkpoint instance which is not later than `notLaterThan`.
Optional<CheckpointMetaData>	readLastCheckpointFile(Engine engine)	Returns information about the most recent checkpoint.
void	writeLastCheckpointFile(Engine engine, CheckpointMetaData checkpointMetaData)	Write the given data to last checkpoint metadata file.

Methods inherited from class java.lang.Object

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

Field Details

LAST_CHECKPOINT_FILE_NAME

public static final String LAST_CHECKPOINT_FILE_NAME

The name of the last checkpoint file

See Also:

• Constant Field Values

Constructor Details

Checkpointer

public Checkpointer(Path logPath)

Method Details

checkpoint

public static void checkpoint(Engine engine,
 Clock clock,
 SnapshotImpl snapshot)
                       throws TableNotFoundException,
IOException

Throws:

TableNotFoundException

IOException

getLatestCompleteCheckpointFromList

public static Optional<CheckpointInstance> getLatestCompleteCheckpointFromList(List<CheckpointInstance> instances,
 CheckpointInstance notLaterThan)

Given a list of checkpoint files, pick the latest complete checkpoint instance which is not later than `notLaterThan`.

findLastCompleteCheckpointBefore

public static Optional<CheckpointInstance> findLastCompleteCheckpointBefore(Engine engine,
 Path tableLogPath,
 long version)

Find the last complete checkpoint before (strictly less than) a given version.

findLastCompleteCheckpointBeforeHelper

public static Tuple2<Optional<CheckpointInstance>,Long> findLastCompleteCheckpointBeforeHelper(Engine engine,
 Path tableLogPath,
 long version)

Helper method for `findLastCompleteCheckpointBefore` which also return the number of files searched. This helps in testing

readLastCheckpointFile

public Optional<CheckpointMetaData> readLastCheckpointFile(Engine engine)

Returns information about the most recent checkpoint.

writeLastCheckpointFile

public void writeLastCheckpointFile(Engine engine,
 CheckpointMetaData checkpointMetaData)
                             throws IOException

Write the given data to last checkpoint metadata file.

Parameters:

engine - Engine instance to use for writing

checkpointMetaData - Checkpoint metadata to write

Throws:

IOException - For any I/O issues.