org.apache.spark.util

Class ShutdownHookManager

Object

org.apache.spark.util.ShutdownHookManager

public class ShutdownHookManager
extends Object

Various utility methods used by Spark.

Constructor Summary

Constructors

Constructor and Description
ShutdownHookManager()

Method Summary

Modifier and Type	Method and Description
static Object	addShutdownHook(scala.Function0<scala.runtime.BoxedUnit> hook) Adds a shutdown hook with default priority.
static Object	addShutdownHook(int priority, scala.Function0<scala.runtime.BoxedUnit> hook) Adds a shutdown hook with the given priority.
static int	DEFAULT_SHUTDOWN_PRIORITY()
static boolean	hasRootAsShutdownDeleteDir(java.io.File file)
static boolean	hasShutdownDeleteDir(java.io.File file)
static boolean	inShutdown() Detect whether this thread might be executing a shutdown hook.
static void	registerShutdownDeleteDir(java.io.File file)
static void	removeShutdownDeleteDir(java.io.File file)
static boolean	removeShutdownHook(Object ref) Remove a previously installed shutdown hook.
static int	SPARK_CONTEXT_SHUTDOWN_PRIORITY() The shutdown priority of the SparkContext instance.
static int	TEMP_DIR_SHUTDOWN_PRIORITY() The shutdown priority of temp directory must be lower than the SparkContext shutdown priority.

Methods inherited from class Object

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

Constructor Detail

ShutdownHookManager

public ShutdownHookManager()

Method Detail

DEFAULT_SHUTDOWN_PRIORITY

public static int DEFAULT_SHUTDOWN_PRIORITY()

SPARK_CONTEXT_SHUTDOWN_PRIORITY

public static int SPARK_CONTEXT_SHUTDOWN_PRIORITY()

The shutdown priority of the SparkContext instance. This is lower than the default priority, so that by default hooks are run before the context is shut down.

Returns:

(undocumented)

TEMP_DIR_SHUTDOWN_PRIORITY

public static int TEMP_DIR_SHUTDOWN_PRIORITY()

The shutdown priority of temp directory must be lower than the SparkContext shutdown priority. Otherwise cleaning the temp directories while Spark jobs are running can throw undesirable errors at the time of shutdown.

Returns:

(undocumented)

registerShutdownDeleteDir

public static void registerShutdownDeleteDir(java.io.File file)

removeShutdownDeleteDir

public static void removeShutdownDeleteDir(java.io.File file)

hasShutdownDeleteDir

public static boolean hasShutdownDeleteDir(java.io.File file)

hasRootAsShutdownDeleteDir

public static boolean hasRootAsShutdownDeleteDir(java.io.File file)

inShutdown

public static boolean inShutdown()

Detect whether this thread might be executing a shutdown hook. Will always return true if the current thread is a running a shutdown hook but may spuriously return true otherwise (e.g. if System.exit was just called by a concurrent thread).

Currently, this detects whether the JVM is shutting down by Runtime#addShutdownHook throwing an IllegalStateException.

Returns:

(undocumented)

addShutdownHook

public static Object addShutdownHook(scala.Function0<scala.runtime.BoxedUnit> hook)

Adds a shutdown hook with default priority.

Parameters:

hook - The code to run during shutdown.

Returns:

A handle that can be used to unregister the shutdown hook.

addShutdownHook

public static Object addShutdownHook(int priority,
                                     scala.Function0<scala.runtime.BoxedUnit> hook)

Adds a shutdown hook with the given priority. Hooks with lower priority values run first.

Parameters:

hook - The code to run during shutdown.

priority - (undocumented)

Returns:

A handle that can be used to unregister the shutdown hook.

removeShutdownHook

public static boolean removeShutdownHook(Object ref)

Remove a previously installed shutdown hook.

Parameters:

ref - A handle returned by addShutdownHook.

Returns:

Whether the hook was removed.