org.apache.samza.checkpoint

Class CheckpointV2

java.lang.Object

org.apache.samza.checkpoint.CheckpointV2

All Implemented Interfaces:

Checkpoint

public class CheckpointV2
extends java.lang.Object
implements Checkpoint

A checkpoint is a mapping of all the streams a job is consuming and the most recent current offset for each. It is used to restore a StreamTask, either as part of a job restart or as part of restarting a failed container within a running job.

Field Summary

Fields

Modifier and Type	Field and Description
static short	CHECKPOINT_VERSION

Constructor Summary

Constructors

Constructor and Description
CheckpointV2(CheckpointId checkpointId, java.util.Map<SystemStreamPartition,java.lang.String> inputOffsets, java.util.Map<java.lang.String,java.util.Map<java.lang.String,java.lang.String>> stateCheckpoints) Constructs the checkpoint with separated input and state offsets

Method Summary

Modifier and Type	Method and Description
boolean	equals(java.lang.Object o)
CheckpointId	getCheckpointId() Gets the checkpoint id for the checkpoint
java.util.Map<SystemStreamPartition,java.lang.String>	getOffsets() Gets a unmodifiable view of the current input SystemStreamPartition offsets.
java.util.Map<java.lang.String,java.util.Map<java.lang.String,java.lang.String>>	getStateCheckpointMarkers() Gets the state checkpoint markers for all stores for each configured state backend.
short	getVersion() Gets the version number of the Checkpoint
int	hashCode()
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

CHECKPOINT_VERSION

public static final short CHECKPOINT_VERSION

See Also:

Constant Field Values

Constructor Detail

CheckpointV2

public CheckpointV2(CheckpointId checkpointId,
                    java.util.Map<SystemStreamPartition,java.lang.String> inputOffsets,
                    java.util.Map<java.lang.String,java.util.Map<java.lang.String,java.lang.String>> stateCheckpoints)

Constructs the checkpoint with separated input and state offsets

Parameters:

checkpointId - CheckpointId associated with this checkpoint

inputOffsets - Map of Samza system stream partition to offset of the checkpoint

stateCheckpoints - Map of state backend factory name to map of local state store names to state checkpoints

Method Detail

getVersion

public short getVersion()

Description copied from interface: Checkpoint

Gets the version number of the Checkpoint

Specified by:

getVersion in interface Checkpoint

Returns:

Short indicating the version number

getCheckpointId

public CheckpointId getCheckpointId()

Gets the checkpoint id for the checkpoint

Returns:

The timestamp based checkpoint identifier associated with the checkpoint

getOffsets

public java.util.Map<SystemStreamPartition,java.lang.String> getOffsets()

Gets a unmodifiable view of the current input SystemStreamPartition offsets.

Specified by:

getOffsets in interface Checkpoint

Returns:

An unmodifiable map of input SystemStreamPartitions to their recorded offsets.

getStateCheckpointMarkers

public java.util.Map<java.lang.String,java.util.Map<java.lang.String,java.lang.String>> getStateCheckpointMarkers()

Gets the state checkpoint markers for all stores for each configured state backend. Note: We don't add this method to the Checkpoint interface since it is difficult to implement it for CheckpointV1 without changing the underlying serialization format - the changelog SSP offsets are serialized in the same way as input offsets, and at deserialization time we don't have enough information (e.g. configs) to decide whether a particular entry is for an input SSP or a changelog SSP.

Returns:

Map of state backend factory name to map of local state store names to state checkpoint markers

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object