Timer (Java 2 Platform Ent. Ed. v1.4)

javax.management.timer
Class Timer
java.lang.Object
  javax.management.NotificationBroadcasterSupport
      javax.management.timer.Timer
All Implemented Interfaces:
MBeanRegistration, NotificationBroadcaster, NotificationEmitter, TimerMBean

public class Timer
extends NotificationBroadcasterSupport
implements TimerMBean, MBeanRegistration

Provides the implementation of the timer MBean. The timer MBean sends out an alarm at a specified time that wakes up all the listeners registered to receive timer notifications.
This class manages a list of dated timer notifications. A method allows users to add/remove as many notifications as required. When a timer notification is emitted by the timer and becomes obsolete, it is automatically removed from the list of timer notifications.
Additional timer notifications can be added into regularly repeating notifications.
Note:

All notifications before the time when the addNotification method is called are ignored, irrespective of the sendPastNotifications flag.
When sending timer notifications, the timer updates the notification sequence number irrespective of the notification type.
The timer service relies on the system date of the host where the Timer class is loaded. Listeners may receive untimely notifications if their host has a different system date. To avoid such problems, synchronize the system date of all host machines where timing is needed.
The default behaviour for periodic notifications is fixed-delay execution, as specified in Timer. In order to use fixed-rate execution, use the overloaded addNotification(String, String, Object, Date, long, long, boolean) method.
Notification listeners are potentially all executed in the same thread. Therefore, they should execute rapidly to avoid holding up other listeners or perturbing the regularity of fixed-delay executions. See NotificationBroadcasterSupport.

Version:

4.47 10/03/02

Author:

Sun Microsystems, Inc

Field Summary
static long ONE_DAY
          Number of milliseconds in one day.
static long ONE_HOUR
          Number of milliseconds in one hour.
static long ONE_MINUTE
          Number of milliseconds in one minute.
static long ONE_SECOND
          Number of milliseconds in one second.
static long ONE_WEEK
          Number of milliseconds in one week.

Constructor Summary

Timer()
          Default constructor.

Method Summary
Integer addNotification(String type, String message, Object userData, Date date)
          Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date and a null period and number of occurences.
Integer addNotification(String type, String message, Object userData, Date date, long period)
          Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date and period and a null number of occurences.
Integer addNotification(String type, String message, Object userData, Date date, long period, long nbOccurences)
          Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date, period and number of occurences.
Integer addNotification(String type, String message, Object userData, Date date, long period, long nbOccurences, boolean fixedRate)
          Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date, period and number of occurences.
Vector getAllNotificationIDs()
          Gets all timer notification identifiers registered into the list of notifications.
Date getDate(Integer id)
          Gets a copy of the date associated to a timer notification.
Boolean getFixedRate(Integer id)
          Gets a copy of the flag indicating whether a peridic notification is executed at fixed-delay or at fixed-rate.
int getNbNotifications()
          Gets the number of timer notifications registered into the list of notifications.
Long getNbOccurences(Integer id)
          Gets a copy of the remaining number of occurences associated to a timer notification.
Vector getNotificationIDs(String type)
          Gets all the identifiers of timer notifications corresponding to the specified type.
String getNotificationMessage(Integer id)
          Gets the timer notification detailed message corresponding to the specified identifier.
String getNotificationType(Integer id)
          Gets the timer notification type corresponding to the specified identifier.
Object getNotificationUserData(Integer id)
          Gets the timer notification user data object corresponding to the specified identifier.
Long getPeriod(Integer id)
          Gets a copy of the period (in milliseconds) associated to a timer notification.
boolean getSendPastNotifications()
          Gets the flag indicating whether or not the timer sends past notifications.
boolean isActive()
          Tests whether the timer MBean is active.
boolean isEmpty()
          Tests whether the list of timer notifications is empty.
void postDeregister()
          Allows the timer MBean to perform any operations needed after having been unregistered by the MBean server.
void postRegister(Boolean registrationDone)
          Allows the timer MBean to perform any operations needed after having been registered in the MBean server or after the registration has failed.
void preDeregister()
          Allows the timer MBean to perform any operations it needs before being unregistered by the MBean server.
ObjectName preRegister(MBeanServer server, ObjectName name)
          Allows the timer MBean to perform any operations it needs before being registered in the MBean server.
void removeAllNotifications()
          Removes all the timer notifications from the list of notifications and resets the counter used to update the timer notification identifiers.
void removeNotification(Integer id)
          Removes the timer notification corresponding to the specified identifier from the list of notifications.
void removeNotifications(String type)
          Removes all the timer notifications corresponding to the specified type from the list of notifications.
void setSendPastNotifications(boolean value)
          Sets the flag indicating whether the timer sends past notifications or not.
void start()
          Starts the timer.
void stop()
          Stops the timer.

Methods inherited from class javax.management.NotificationBroadcasterSupport
addNotificationListener, getNotificationInfo, handleNotification, removeNotificationListener, removeNotificationListener, sendNotification

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ONE_SECOND
public static final long ONE_SECOND
Number of milliseconds in one second. Useful constant for the addNotification method.

See Also:
Constant Field Values

ONE_MINUTE
public static final long ONE_MINUTE
Number of milliseconds in one minute. Useful constant for the addNotification method.

See Also:
Constant Field Values

ONE_HOUR
public static final long ONE_HOUR
Number of milliseconds in one hour. Useful constant for the addNotification method.

See Also:
Constant Field Values

ONE_DAY
public static final long ONE_DAY
Number of milliseconds in one day. Useful constant for the addNotification method.

See Also:
Constant Field Values

ONE_WEEK
public static final long ONE_WEEK
Number of milliseconds in one week. Useful constant for the addNotification method.

See Also:
Constant Field Values

Constructor Detail

Timer
public Timer()
Default constructor.

Method Detail

preRegister
public ObjectName preRegister(MBeanServer server,
                              ObjectName name)
                       throws Exception
Allows the timer MBean to perform any operations it needs before being registered in the MBean server.
Not used in this context.

Specified by:
preRegister in interface MBeanRegistration

Parameters:
server - The MBean server in which the timer MBean will be registered.
name - The object name of the timer MBean.
Returns:
The name of the timer MBean registered.
Throws:
Exception

postRegister
public void postRegister(Boolean registrationDone)
Allows the timer MBean to perform any operations needed after having been registered in the MBean server or after the registration has failed.
Not used in this context.

Specified by:
postRegister in interface MBeanRegistration

Parameters:
registrationDone - Indicates whether or not the MBean has been successfully registered in the MBean server. The value false means that the registration phase has failed.

preDeregister
public void preDeregister()
                   throws Exception
Allows the timer MBean to perform any operations it needs before being unregistered by the MBean server.
Stops the timer.

Specified by:
preDeregister in interface MBeanRegistration

Throws:
Exception

postDeregister
public void postDeregister()
Allows the timer MBean to perform any operations needed after having been unregistered by the MBean server.
Not used in this context.

Specified by:
postDeregister in interface MBeanRegistration

start
public void start()
Starts the timer.
If there is one or more timer notifications before the time in the list of notifications, the notification is sent according to the sendPastNotifications flag and then, updated according to its period and remaining number of occurences. If the timer notification date remains earlier than the current date, this notification is just removed from the list of notifications.

Specified by:
start in interface TimerMBean

stop
public void stop()
Stops the timer.

Specified by:
stop in interface TimerMBean

addNotification
public Integer addNotification(String type,
                               String message,
                               Object userData,
                               Date date,
                               long period,
                               long nbOccurences,
                               boolean fixedRate)
                        throws IllegalArgumentException
Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date, period and number of occurences.
If the timer notification to be inserted has a date that is before the current date, the method behaves as if the specified date were the current date.
For once-off notifications, the notification is delivered immediately.
For periodic notifications, the first notification is delivered immediately and the subsequent ones are spaced as specified by the period parameter.
Note that once the timer notification has been added into the list of notifications, its associated date, period and number of occurences cannot be updated.
In the case of a periodic notification, the value of parameter fixedRate is used to specify the execution scheme, as specified in Timer.

Specified by:
addNotification in interface TimerMBean

Parameters:
type - The timer notification type.
message - The timer notification detailed message.
userData - The timer notification user data object.
date - The date when the notification occurs.
period - The period of the timer notification (in milliseconds).
nbOccurences - The total number the timer notification will be emitted.
fixedRate - If true and if the notification is periodic, the notification is scheduled with a fixed-rate execution scheme. If false and if the notification is periodic, the notification is scheduled with a fixed-delay execution scheme. Ignored if the notification is not periodic.
Returns:
The identifier of the new created timer notification.
Throws:
IllegalArgumentException - The period or the number of occurences is negative
See Also:
addNotification(String, String, Object, Date, long, long)

addNotification
public Integer addNotification(String type,
                               String message,
                               Object userData,
                               Date date,
                               long period,
                               long nbOccurences)
                        throws IllegalArgumentException
Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date, period and number of occurences.
If the timer notification to be inserted has a date that is before the current date, the method behaves as if the specified date were the current date.
For once-off notifications, the notification is delivered immediately.
For periodic notifications, the first notification is delivered immediately and the subsequent ones are spaced as specified by the period parameter.
Note that once the timer notification has been added into the list of notifications, its associated date, period and number of occurences cannot be updated.
In the case of a periodic notification, uses a fixed-delay execution scheme, as specified in Timer. In order to use a fixed-rate execution scheme, use addNotification(String, String, Object, Date, long, long, boolean) instead.

Specified by:
addNotification in interface TimerMBean

Parameters:
type - The timer notification type.
message - The timer notification detailed message.
userData - The timer notification user data object.
date - The date when the notification occurs.
period - The period of the timer notification (in milliseconds).
nbOccurences - The total number the timer notification will be emitted.
Returns:
The identifier of the new created timer notification.
Throws:
IllegalArgumentException - The period or the number of occurences is negative
See Also:
addNotification(String, String, Object, Date, long, long, boolean)

addNotification
public Integer addNotification(String type,
                               String message,
                               Object userData,
                               Date date,
                               long period)
                        throws IllegalArgumentException
Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date and period and a null number of occurences.
The timer notification will repeat continuously using the timer period using a fixed-delay execution scheme, as specified in Timer. In order to use a fixed-rate execution scheme, use addNotification(String, String, Object, Date, long, long, boolean) instead.
If the timer notification to be inserted has a date that is before the current date, the method behaves as if the specified date were the current date. The first notification is delivered immediately and the subsequent ones are spaced as specified by the period parameter.

Specified by:
addNotification in interface TimerMBean

Parameters:
type - The timer notification type.
message - The timer notification detailed message.
userData - The timer notification user data object.
date - The date when the notification occurs.
period - The period of the timer notification (in milliseconds).
Returns:
The identifier of the new created timer notification.
Throws:
IllegalArgumentException - The period is negative or the date notification is before the current date.

addNotification
public Integer addNotification(String type,
                               String message,
                               Object userData,
                               Date date)
                        throws IllegalArgumentException
Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date and a null period and number of occurences.
The timer notification will be handled once at the specified date.
If the timer notification to be inserted has a date that is before the current date, the method behaves as if the specified date were the current date and the notification is delivered immediately.

Specified by:
addNotification in interface TimerMBean

Parameters:
type - The timer notification type.
message - The timer notification detailed message.
userData - The timer notification user data object.
date - The date when the notification occurs.
Returns:
The identifier of the new created timer notification.
Throws:
IllegalArgumentException - The date notification is before the current date.

removeNotification
public void removeNotification(Integer id)
                        throws InstanceNotFoundException
Removes the timer notification corresponding to the specified identifier from the list of notifications.

Specified by:
removeNotification in interface TimerMBean

Parameters:
id - The timer notification identifier.
Throws:
InstanceNotFoundException - The specified identifier does not correspond to any timer notification in the list of notifications of this timer MBean.

removeNotifications
public void removeNotifications(String type)
                         throws InstanceNotFoundException
Removes all the timer notifications corresponding to the specified type from the list of notifications.

Specified by:
removeNotifications in interface TimerMBean

Parameters:
type - The timer notification type.
Throws:
InstanceNotFoundException - The specified type does not correspond to any timer notification in the list of notifications of this timer MBean.

removeAllNotifications
public void removeAllNotifications()
Removes all the timer notifications from the list of notifications and resets the counter used to update the timer notification identifiers.

Specified by:
removeAllNotifications in interface TimerMBean

getNbNotifications
public int getNbNotifications()
Gets the number of timer notifications registered into the list of notifications.

Specified by:
getNbNotifications in interface TimerMBean

Returns:
The number of timer notifications.

getAllNotificationIDs
public Vector getAllNotificationIDs()
Gets all timer notification identifiers registered into the list of notifications.

Specified by:
getAllNotificationIDs in interface TimerMBean

Returns:
A vector of Integer objects containing all the timer notification identifiers.
The vector is empty if there is no timer notification registered for this timer MBean.

getNotificationIDs
public Vector getNotificationIDs(String type)
Gets all the identifiers of timer notifications corresponding to the specified type.

Specified by:
getNotificationIDs in interface TimerMBean

Parameters:
type - The timer notification type.
Returns:
A vector of Integer objects containing all the identifiers of timer notifications with the specified type.
The vector is empty if there is no timer notifications registered for this timer MBean with the specified type.

getNotificationType
public String getNotificationType(Integer id)
Gets the timer notification type corresponding to the specified identifier.

Specified by:
getNotificationType in interface TimerMBean

Parameters:
id - The timer notification identifier.
Returns:
The timer notification type or null if the identifier is not mapped to any timer notification registered for this timer MBean.

getNotificationMessage
public String getNotificationMessage(Integer id)
Gets the timer notification detailed message corresponding to the specified identifier.

Specified by:
getNotificationMessage in interface TimerMBean

Parameters:
id - The timer notification identifier.
Returns:
The timer notification detailed message or null if the identifier is not mapped to any timer notification registered for this timer MBean.

getNotificationUserData
public Object getNotificationUserData(Integer id)
Gets the timer notification user data object corresponding to the specified identifier.

Specified by:
getNotificationUserData in interface TimerMBean

Parameters:
id - The timer notification identifier.
Returns:
The timer notification user data object or null if the identifier is not mapped to any timer notification registered for this timer MBean.

getDate
public Date getDate(Integer id)
Gets a copy of the date associated to a timer notification.

Specified by:
getDate in interface TimerMBean

Parameters:
id - The timer notification identifier.
Returns:
A copy of the date or null if the identifier is not mapped to any timer notification registered for this timer MBean.

getPeriod
public Long getPeriod(Integer id)
Gets a copy of the period (in milliseconds) associated to a timer notification.

Specified by:
getPeriod in interface TimerMBean

Parameters:
id - The timer notification identifier.
Returns:
A copy of the period or null if the identifier is not mapped to any timer notification registered for this timer MBean.

getNbOccurences
public Long getNbOccurences(Integer id)
Gets a copy of the remaining number of occurences associated to a timer notification.

Specified by:
getNbOccurences in interface TimerMBean

Parameters:
id - The timer notification identifier.
Returns:
A copy of the remaining number of occurences or null if the identifier is not mapped to any timer notification registered for this timer MBean.

getFixedRate
public Boolean getFixedRate(Integer id)
Gets a copy of the flag indicating whether a peridic notification is executed at fixed-delay or at fixed-rate.

Specified by:
getFixedRate in interface TimerMBean

Parameters:
id - The timer notification identifier.
Returns:
A copy of the flag indicating whether a peridic notification is executed at fixed-delay or at fixed-rate.

getSendPastNotifications
public boolean getSendPastNotifications()
Gets the flag indicating whether or not the timer sends past notifications.
The default value of the past notifications sending on/off flag is false.

Specified by:
getSendPastNotifications in interface TimerMBean

Returns:
The past notifications sending on/off flag value.
See Also:
setSendPastNotifications(boolean)

setSendPastNotifications
public void setSendPastNotifications(boolean value)
Sets the flag indicating whether the timer sends past notifications or not.
The default value of the past notifications sending on/off flag is false.

Specified by:
setSendPastNotifications in interface TimerMBean

Parameters:
value - The past notifications sending on/off flag value.
See Also:
getSendPastNotifications()

isActive
public boolean isActive()
Tests whether the timer MBean is active. A timer MBean is marked active when the start method is called. It becomes inactive when the stop method is called.
The default value of the active on/off flag is false.

Specified by:
isActive in interface TimerMBean

Returns:
true if the timer MBean is active, false otherwise.

isEmpty
public boolean isEmpty()
Tests whether the list of timer notifications is empty.

Specified by:
isEmpty in interface TimerMBean

Returns:
true if the list of timer notifications is empty, false otherwise.

Submit a bug or feature
Copyright 2003 Sun Microsystems, Inc. All rights reserved.

Field Summary
static long	ONE_DAY Number of milliseconds in one day.
static long	ONE_HOUR Number of milliseconds in one hour.
static long	ONE_MINUTE Number of milliseconds in one minute.
static long	ONE_SECOND Number of milliseconds in one second.
static long	ONE_WEEK Number of milliseconds in one week.

Method Summary
Integer	addNotification(String type, String message, Object userData, Date date) Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date and a null period and number of occurences.
Integer	addNotification(String type, String message, Object userData, Date date, long period) Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date and period and a null number of occurences.
Integer	addNotification(String type, String message, Object userData, Date date, long period, long nbOccurences) Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date, period and number of occurences.
Integer	addNotification(String type, String message, Object userData, Date date, long period, long nbOccurences, boolean fixedRate) Creates a new timer notification with the specified type, message and userData and inserts it into the list of notifications with a given date, period and number of occurences.
Vector	getAllNotificationIDs() Gets all timer notification identifiers registered into the list of notifications.
Date	getDate(Integer id) Gets a copy of the date associated to a timer notification.
Boolean	getFixedRate(Integer id) Gets a copy of the flag indicating whether a peridic notification is executed at fixed-delay or at fixed-rate.
int	getNbNotifications() Gets the number of timer notifications registered into the list of notifications.
Long	getNbOccurences(Integer id) Gets a copy of the remaining number of occurences associated to a timer notification.
Vector	getNotificationIDs(String type) Gets all the identifiers of timer notifications corresponding to the specified type.
String	getNotificationMessage(Integer id) Gets the timer notification detailed message corresponding to the specified identifier.
String	getNotificationType(Integer id) Gets the timer notification type corresponding to the specified identifier.
Object	getNotificationUserData(Integer id) Gets the timer notification user data object corresponding to the specified identifier.
Long	getPeriod(Integer id) Gets a copy of the period (in milliseconds) associated to a timer notification.
boolean	getSendPastNotifications() Gets the flag indicating whether or not the timer sends past notifications.
boolean	isActive() Tests whether the timer MBean is active.
boolean	isEmpty() Tests whether the list of timer notifications is empty.
void	postDeregister() Allows the timer MBean to perform any operations needed after having been unregistered by the MBean server.
void	postRegister(Boolean registrationDone) Allows the timer MBean to perform any operations needed after having been registered in the MBean server or after the registration has failed.
void	preDeregister() Allows the timer MBean to perform any operations it needs before being unregistered by the MBean server.
ObjectName	preRegister(MBeanServer server, ObjectName name) Allows the timer MBean to perform any operations it needs before being registered in the MBean server.
void	removeAllNotifications() Removes all the timer notifications from the list of notifications and resets the counter used to update the timer notification identifiers.
void	removeNotification(Integer id) Removes the timer notification corresponding to the specified identifier from the list of notifications.
void	removeNotifications(String type) Removes all the timer notifications corresponding to the specified type from the list of notifications.
void	setSendPastNotifications(boolean value) Sets the flag indicating whether the timer sends past notifications or not.
void	start() Starts the timer.
void	stop() Stops the timer.

javax.management.timer Class Timer

Constructor Summary

ONE_SECOND

ONE_MINUTE

ONE_HOUR

ONE_DAY

ONE_WEEK

Timer

preRegister

postRegister

preDeregister

postDeregister

start

stop

addNotification

addNotification

addNotification

addNotification

removeNotification

removeNotifications

removeAllNotifications

getNbNotifications

getAllNotificationIDs

getNotificationIDs

getNotificationType

getNotificationMessage

getNotificationUserData

getDate

getPeriod

getNbOccurences

getFixedRate

getSendPastNotifications

setSendPastNotifications

isActive

isEmpty

javax.management.timer
Class Timer