Package org.apache.hadoop.service

Class ServiceOperations

java.lang.Object

org.apache.hadoop.service.ServiceOperations

@Public
@Evolving
public final class ServiceOperations
extends Object

This class contains a set of methods to work with services, especially to walk them through their lifecycle.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	org.apache.hadoop.service.ServiceOperations.ServiceListeners	Class to manage a list of ServiceStateChangeListener instances, including a notification loop that is robust against changes to the list during the notification process.

Method Summary

Modifier and Type	Method	Description
static void	stop(Service service)	Stop a service.
static Exception	stopQuietly(org.apache.commons.logging.Log log, Service service)	Deprecated. to be removed with 3.4.0.
static Exception	stopQuietly(Service service)	Stop a service; if it is null do nothing.
static Exception	stopQuietly(org.slf4j.Logger log, Service service)	Stop a service; if it is null do nothing.

Methods inherited from class java.lang.Object

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

Method Details

stop

public static void stop(Service service)

Stop a service.

Do nothing if the service is null or not in a state in which it can be/needs to be stopped.

The service state is checked before the operation begins. This process is not thread safe.

Parameters:

service - a service or null

stopQuietly

public static Exception stopQuietly(Service service)

Stop a service; if it is null do nothing. Exceptions are caught and logged at warn level. (but not Throwables). This operation is intended to be used in cleanup operations

Parameters:

service - a service; may be null

Returns:

any exception that was caught; null if none was.

stopQuietly

@Deprecated
public static Exception stopQuietly(org.apache.commons.logging.Log log,
 Service service)

Deprecated.

to be removed with 3.4.0. Use stopQuietly(Logger, Service) instead.

Stop a service; if it is null do nothing. Exceptions are caught and logged at warn level. (but not Throwables). This operation is intended to be used in cleanup operations

Parameters:

log - the log to warn at

service - a service; may be null

Returns:

any exception that was caught; null if none was.

stopQuietly

public static Exception stopQuietly(org.slf4j.Logger log,
 Service service)

Stop a service; if it is null do nothing. Exceptions are caught and logged at warn level. (but not Throwables). This operation is intended to be used in cleanup operations

Parameters:

log - the log to warn at

service - a service; may be null

Returns:

any exception that was caught; null if none was.

See Also:

• stopQuietly(Service)