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

[Expand]
Inherited Constants
From class javax.management.monitor.Monitor
[Expand]
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.
[Expand]
Inherited Methods
From class javax.management.monitor.Monitor
From class javax.management.NotificationBroadcasterSupport
From class java.lang.Object
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.
See Also

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.
See Also

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.