org.apache.flink.runtime.util

Class JvmShutdownSafeguard

java.lang.Object

java.lang.Thread

org.apache.flink.runtime.util.JvmShutdownSafeguard

All Implemented Interfaces:

Runnable

public class JvmShutdownSafeguard
extends Thread

A utility that guards against blocking shutdown hooks that block JVM shutdown.

When the JVM shuts down cleanly (SIGTERM or System.exit(int)) it runs all installed shutdown hooks. It is possible that any of the shutdown hooks blocks, which causes the JVM to get stuck and not exit at all.

This utility installs a shutdown hook that forcibly terminates the JVM if it is still alive a certain time after clean shutdown was initiated. Even if some shutdown hooks block, the JVM will terminate within a certain time.

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Thread.State, Thread.UncaughtExceptionHandler

Field Summary

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Method Summary

Modifier and Type	Method and Description
static void	installAsShutdownHook(org.slf4j.Logger logger) Installs the safeguard shutdown hook.
static void	installAsShutdownHook(org.slf4j.Logger logger, long delayMillis) Installs the safeguard shutdown hook.
void	run()

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Method Detail

run

public void run()

Specified by:

run in interface Runnable

Overrides:

run in class Thread

installAsShutdownHook

public static void installAsShutdownHook(org.slf4j.Logger logger)

Installs the safeguard shutdown hook. The maximum time that the JVM is allowed to spend on shutdown before being killed is five seconds.

Parameters:

logger - The logger to log errors to.

installAsShutdownHook

public static void installAsShutdownHook(org.slf4j.Logger logger,
                                         long delayMillis)

Installs the safeguard shutdown hook. The maximum time that the JVM is allowed to spend on shutdown before being killed is the given number of milliseconds.

Parameters:

logger - The logger to log errors to.

delayMillis - The delay (in milliseconds) to wait after clean shutdown was stared, before forcibly terminating the JVM.