Package org.apache.kafka.streams.processor.internals

Class StateDirectory

java.lang.Object

org.apache.kafka.streams.processor.internals.StateDirectory

public class StateDirectory
extends Object

Manages the directories where the state of Tasks owned by a StreamThread are stored. Handles creation/locking/unlocking/cleaning of the Task Directories. This class is not thread-safe.

Constructor Summary

Constructors

Constructor	Description
StateDirectory(StreamsConfig config, org.apache.kafka.common.utils.Time time, boolean hasPersistentStores)	Ensures that the state base directory as well as the application's sub-directory are created.

Method Summary

Modifier and Type	Method	Description
void	clean()
void	cleanRemovedTasks(long cleanupDelayMs)	Remove the directories for any TaskIds that are no-longer owned by this StreamThread and aren't locked by either another process or another StreamThread
File	directoryForTask(TaskId taskId)	Get or create the directory for the provided TaskId.

Methods inherited from class java.lang.Object

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

Constructor Detail

StateDirectory

public StateDirectory(StreamsConfig config,
                      org.apache.kafka.common.utils.Time time,
                      boolean hasPersistentStores)

Ensures that the state base directory as well as the application's sub-directory are created.

Parameters:

config - streams application configuration to read the root state directory path

time - system timer used to execute periodic cleanup procedure

hasPersistentStores - only when the application's topology does have stores persisted on local file system, we would go ahead and auto-create the corresponding application / task / store directories whenever necessary; otherwise no directories would be created.

Throws:

ProcessorStateException - if the base state directory or application state directory does not exist and could not be created when hasPersistentStores is enabled.

Method Detail

directoryForTask

public File directoryForTask(TaskId taskId)

Get or create the directory for the provided TaskId.

Returns:

directory for the TaskId

Throws:

ProcessorStateException - if the task directory does not exists and could not be created

clean

public void clean()

cleanRemovedTasks

public void cleanRemovedTasks(long cleanupDelayMs)

Remove the directories for any TaskIds that are no-longer owned by this StreamThread and aren't locked by either another process or another StreamThread

Parameters:

cleanupDelayMs - only remove directories if they haven't been modified for at least this amount of time (milliseconds)