public class

GaugeMonitor

extends Monitor
implements GaugeMonitorMBean

java.lang.Object
↳	javax.management.NotificationBroadcasterSupport
	↳	javax.management.monitor.Monitor
		↳	javax.management.monitor.GaugeMonitor

Class Overview

Defines a monitor MBean designed to observe the values of a gauge attribute.

A gauge monitor observes an attribute that is continuously variable with time. A gauge monitor sends notifications as follows:

if the attribute value is increasing and becomes equal to or greater than the high threshold value, a threshold high notification is sent. The notify high flag must be set to true.
Subsequent crossings of the high threshold value do not cause further notifications unless the attribute value becomes equal to or less than the low threshold value.
if the attribute value is decreasing and becomes equal to or less than the low threshold value, a threshold low notification is sent. The notify low flag must be set to true.
Subsequent crossings of the low threshold value do not cause further notifications unless the attribute value becomes equal to or greater than the high threshold value.

This provides a hysteresis mechanism to avoid repeated triggering of notifications when the attribute value makes small oscillations around the high or low threshold value.

If the gauge difference mode is used, the value of the derived gauge is calculated as the difference between the observed gauge values for two successive observations.
The derived gauge value (V[t]) is calculated using the following method:

V[t] = gauge[t] - gauge[t-GP]

This implementation of the gauge monitor requires the observed attribute to be of the type integer or floating-point (Byte, Integer, Short, Long, Float, Double).

Summary

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Inherited Constants

From class javax.management.monitor.Monitor

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Inherited Fields

From class javax.management.monitor.Monitor

Public Constructors
	GaugeMonitor() Default constructor.

Public Methods
synchronized Number	getDerivedGauge() This method is deprecated. As of JMX 1.2, replaced by `getDerivedGauge(ObjectName)`
synchronized Number	getDerivedGauge(ObjectName object) Gets the derived gauge of the specified object, if this object is contained in the set of observed MBeans, or `null` otherwise.
synchronized long	getDerivedGaugeTimeStamp(ObjectName object) Gets the derived gauge timestamp of the specified object, if this object is contained in the set of observed MBeans, or `0` otherwise.
synchronized long	getDerivedGaugeTimeStamp() This method is deprecated. As of JMX 1.2, replaced by `getDerivedGaugeTimeStamp(ObjectName)`
synchronized boolean	getDifferenceMode() Gets the difference mode flag value common to all observed MBeans.
synchronized Number	getHighThreshold() Gets the high threshold value common to all observed MBeans.
synchronized Number	getLowThreshold() Gets the low threshold value common to all observed MBeans.
MBeanNotificationInfo[]	getNotificationInfo() Returns a `NotificationInfo` object containing the name of the Java class of the notification and the notification types sent by the gauge monitor.
synchronized boolean	getNotifyHigh() Gets the high notification's on/off switch value common to all observed MBeans.
synchronized boolean	getNotifyLow() Gets the low notification's on/off switch value common to all observed MBeans.
synchronized void	setDifferenceMode(boolean value) Sets the difference mode flag value common to all observed MBeans.
synchronized void	setNotifyHigh(boolean value) Sets the high notification's on/off switch value common to all observed MBeans.
synchronized void	setNotifyLow(boolean value) Sets the low notification's on/off switch value common to all observed MBeans.
synchronized void	setThresholds(Number highValue, Number lowValue) Sets the high and the low threshold values common to all observed MBeans.
synchronized void	start() Starts the gauge monitor.
synchronized void	stop() Stops the gauge monitor.

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Inherited Methods

From class javax.management.monitor.Monitor

synchronized void	addObservedObject(ObjectName object) Adds the specified object in the set of observed MBeans, if this object is not already present.
synchronized boolean	containsObservedObject(ObjectName object) Tests whether the specified object is in the set of observed MBeans.
synchronized long	getGranularityPeriod() Gets the granularity period (in milliseconds).
synchronized String	getObservedAttribute() Gets the attribute being observed.
synchronized ObjectName	getObservedObject() This method is deprecated. As of JMX 1.2, replaced by `getObservedObjects()`
synchronized ObjectName[]	getObservedObjects() Returns an array containing the objects being observed.
synchronized boolean	isActive() Tests whether the monitor MBean is active.
void	postDeregister() Allows the monitor MBean to perform any operations needed after having been unregistered by the MBean server.
void	postRegister(Boolean registrationDone) Allows the monitor MBean to perform any operations needed after having been registered in the MBean server or after the registration has failed.
void	preDeregister() Allows the monitor MBean to perform any operations it needs before being unregistered by the MBean server.
ObjectName	preRegister(MBeanServer server, ObjectName name) Allows the monitor MBean to perform any operations it needs before being registered in the MBean server.
synchronized void	removeObservedObject(ObjectName object) Removes the specified object from the set of observed MBeans.
synchronized void	setGranularityPeriod(long period) Sets the granularity period (in milliseconds).
void	setObservedAttribute(String attribute) Sets the attribute to observe.
synchronized void	setObservedObject(ObjectName object) This method is deprecated. As of JMX 1.2, replaced by `addObservedObject(ObjectName)`
abstract void	start() Starts the monitor.
abstract void	stop() Stops the monitor.

From class javax.management.NotificationBroadcasterSupport

From class java.lang.Object

Object	clone() Creates and returns a copy of this object.
boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
void	finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
final Class<?>	getClass() Returns the runtime class of this `Object`.
int	hashCode() Returns a hash code value for the object.
final void	notify() Wakes up a single thread that is waiting on this object's monitor.
final void	notifyAll() Wakes up all threads that are waiting on this object's monitor.
String	toString() Returns a string representation of the object.
final void	wait() Causes the current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object.
final void	wait(long timeout, int nanos) Causes the current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.
final void	wait(long timeout) Causes the current thread to wait until either another thread invokes the `notify()` method or the `notifyAll()` method for this object, or a specified amount of time has elapsed.

From interface javax.management.MBeanRegistration

From interface javax.management.NotificationBroadcaster

From interface javax.management.NotificationEmitter

From interface javax.management.monitor.GaugeMonitorMBean

From interface javax.management.monitor.MonitorMBean

Public Constructors

public GaugeMonitor ()

Default constructor.

Public Methods

public synchronized Number getDerivedGauge ()

This method is deprecated.
As of JMX 1.2, replaced by getDerivedGauge(ObjectName)

Returns the derived gauge of the first object in the set of observed MBeans.

Returns

The derived gauge.

public synchronized Number getDerivedGauge (ObjectName object)

Gets the derived gauge of the specified object, if this object is contained in the set of observed MBeans, or null otherwise.

Parameters

object	the name of the MBean.

Returns

The derived gauge of the specified object.

public synchronized long getDerivedGaugeTimeStamp (ObjectName object)

Gets the derived gauge timestamp of the specified object, if this object is contained in the set of observed MBeans, or 0 otherwise.

Parameters

object	the name of the object whose derived gauge timestamp is to be returned.

Returns

The derived gauge timestamp of the specified object.

public synchronized long getDerivedGaugeTimeStamp ()

This method is deprecated.
As of JMX 1.2, replaced by getDerivedGaugeTimeStamp(ObjectName)

Gets the derived gauge timestamp of the first object in the set of observed MBeans.

Returns

The derived gauge timestamp.

public synchronized boolean getDifferenceMode ()

Gets the difference mode flag value common to all observed MBeans.

Returns

true if the difference mode is used, false otherwise.

public synchronized Number getHighThreshold ()

Gets the high threshold value common to all observed MBeans.

Returns

The high threshold value.

public synchronized Number getLowThreshold ()

Gets the low threshold value common to all observed MBeans.

Returns

The low threshold value.

public MBeanNotificationInfo[] getNotificationInfo ()

Returns a NotificationInfo object containing the name of the Java class of the notification and the notification types sent by the gauge monitor.

Returns

the array of possible notifications.

public synchronized boolean getNotifyHigh ()

Gets the high notification's on/off switch value common to all observed MBeans.

Returns

true if the gauge monitor notifies when exceeding the high threshold, false otherwise.

public synchronized boolean getNotifyLow ()

Gets the low notification's on/off switch value common to all observed MBeans.

Returns

true if the gauge monitor notifies when exceeding the low threshold, false otherwise.

public synchronized void setDifferenceMode (boolean value)

Sets the difference mode flag value common to all observed MBeans.

Parameters

value	The difference mode flag value.

public synchronized void setNotifyHigh (boolean value)

Sets the high notification's on/off switch value common to all observed MBeans.

Parameters

value	The high notification's on/off switch value.

public synchronized void setNotifyLow (boolean value)

Sets the low notification's on/off switch value common to all observed MBeans.

Parameters

value	The low notification's on/off switch value.

public synchronized void setThresholds (Number highValue, Number lowValue)

Sets the high and the low threshold values common to all observed MBeans.

Parameters

highValue	The high threshold value.
lowValue	The low threshold value.

Throws

IllegalArgumentException	The specified high/low threshold is null or the low threshold is greater than the high threshold or the high threshold and the low threshold are not of the same type.

public synchronized void start ()

Starts the gauge monitor.

public synchronized void stop ()

Stops the gauge monitor.

Interfaces

Classes

Exceptions

GaugeMonitor

Class Overview

Summary

Public Constructors

public GaugeMonitor ()

Public Methods

public synchronized Number getDerivedGauge ()

Returns

public synchronized Number getDerivedGauge (ObjectName object)

Parameters

Returns

public synchronized long getDerivedGaugeTimeStamp (ObjectName object)

Parameters

Returns

public synchronized long getDerivedGaugeTimeStamp ()

Returns

public synchronized boolean getDifferenceMode ()

Returns

See Also

public synchronized Number getHighThreshold ()

Returns

See Also

public synchronized Number getLowThreshold ()

Returns

See Also

public MBeanNotificationInfo[] getNotificationInfo ()

Returns

public synchronized boolean getNotifyHigh ()

Returns

See Also

public synchronized boolean getNotifyLow ()

Returns

See Also

public synchronized void setDifferenceMode (boolean value)

Parameters

See Also

public synchronized void setNotifyHigh (boolean value)

Parameters

See Also

public synchronized void setNotifyLow (boolean value)

Parameters

See Also

public synchronized void setThresholds (Number highValue, Number lowValue)

Parameters

Throws

See Also

public synchronized void start ()

public synchronized void stop ()