Class StringMonitor

javax.management.monitor.StringMonitor

All Implemented Interfaces:: MBeanRegistration, MonitorMBean, StringMonitorMBean, NotificationBroadcaster, NotificationEmitter

public class StringMonitor extends Monitor implements StringMonitorMBean

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

A string monitor sends notifications as follows:

if the attribute value matches the string to compare value, a match notification is sent. The notify match flag must be set to true.
Subsequent matchings of the string to compare values do not cause further notifications unless the attribute value differs from the string to compare value.
if the attribute value differs from the string to compare value, a differ notification is sent. The notify differ flag must be set to true.
Subsequent differences from the string to compare value do not cause further notifications unless the attribute value matches the string to compare value.

Since:: 1.5

Field Summary

Fields declared in class Monitor

alreadyNotified, alreadyNotifieds, capacityIncrement, dbgTag, elementCount, OBSERVED_ATTRIBUTE_ERROR_NOTIFIED, OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED, OBSERVED_OBJECT_ERROR_NOTIFIED, RESET_FLAGS_ALREADY_NOTIFIED, RUNTIME_ERROR_NOTIFIED, server

Modifier and Type	Field	Description
`protected int`	`alreadyNotified`	Deprecated. equivalent to `Monitor.alreadyNotifieds`[0].
`protected int[]`	`alreadyNotifieds`	Selected monitor errors that have already been notified.
`protected static final int`	`capacityIncrement`	The amount by which the capacity of the monitor arrays are automatically incremented when their size becomes greater than their capacity.
`protected String`	`dbgTag`	Deprecated. No replacement.
`protected int`	`elementCount`	The number of valid components in the vector of observed objects.
`protected static final int`	`OBSERVED_ATTRIBUTE_ERROR_NOTIFIED`	Flag denoting that a notification has occurred after changing the observed attribute.
`protected static final int`	`OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED`	Flag denoting that a notification has occurred after changing the observed object or the observed attribute.
`protected static final int`	`OBSERVED_OBJECT_ERROR_NOTIFIED`	Flag denoting that a notification has occurred after changing the observed object.
`protected static final int`	`RESET_FLAGS_ALREADY_NOTIFIED`	This flag is used to reset the `alreadyNotifieds` monitor attribute.
`protected static final int`	`RUNTIME_ERROR_NOTIFIED`	Flag denoting that a notification has occurred after changing the observed object or the observed attribute.
`protected MBeanServer`	`server`	Reference to the MBean server.

Constructor Summary

Constructor	Description
`StringMonitor()`	Default constructor.

Method Summary

Modifier and Type	Method	Description
`String`	`getDerivedGauge()`	Deprecated. As of JMX 1.2, replaced by `getDerivedGauge(ObjectName)`
`String`	`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.
`long`	`getDerivedGaugeTimeStamp()`	Deprecated. As of JMX 1.2, replaced by `getDerivedGaugeTimeStamp(ObjectName)`
`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.
`MBeanNotificationInfo[]`	`getNotificationInfo()`	Returns a `NotificationInfo` object containing the name of the Java class of the notification and the notification types sent by the string monitor.
`boolean`	`getNotifyDiffer()`	Gets the differing notification's on/off switch value common to all observed MBeans.
`boolean`	`getNotifyMatch()`	Gets the matching notification's on/off switch value common to all observed MBeans.
`String`	`getStringToCompare()`	Gets the string to compare with the observed attribute common to all observed MBeans.
`void`	`setNotifyDiffer(boolean value)`	Sets the differing notification's on/off switch value common to all observed MBeans.
`void`	`setNotifyMatch(boolean value)`	Sets the matching notification's on/off switch value common to all observed MBeans.
`void`	`setStringToCompare(String value)`	Sets the string to compare with the observed attribute common to all observed MBeans.
`void`	`start()`	Starts the string monitor.
`void`	`stop()`	Stops the string monitor.

Methods declared in class Monitor

addObservedObject, containsObservedObject, getGranularityPeriod, getObservedAttribute, getObservedObject, getObservedObjects, isActive, postDeregister, postRegister, preDeregister, preRegister, removeObservedObject, setGranularityPeriod, setObservedAttribute, setObservedObject

Modifier and Type	Method	Description
`void`	`addObservedObject(ObjectName object)`	Adds the specified object in the set of observed MBeans, if this object is not already present.
`boolean`	`containsObservedObject(ObjectName object)`	Tests whether the specified object is in the set of observed MBeans.
`long`	`getGranularityPeriod()`	Gets the granularity period (in milliseconds).
`String`	`getObservedAttribute()`	Gets the attribute being observed.
`ObjectName`	`getObservedObject()`	Deprecated. As of JMX 1.2, replaced by `Monitor.getObservedObjects()`
`ObjectName[]`	`getObservedObjects()`	Returns an array containing the objects being observed.
`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.
`void`	`removeObservedObject(ObjectName object)`	Removes the specified object from the set of observed MBeans.
`void`	`setGranularityPeriod(long period)`	Sets the granularity period (in milliseconds).
`void`	`setObservedAttribute(String attribute)`	Sets the attribute to observe.
`void`	`setObservedObject(ObjectName object)`	Deprecated. As of JMX 1.2, replaced by `Monitor.addObservedObject(ObjectName)`

Methods declared in class NotificationBroadcasterSupport

addNotificationListener, handleNotification, removeNotificationListener, removeNotificationListener, sendNotification

Modifier and Type	Method	Description
`void`	`addNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback)`	Adds a listener.
`protected void`	`handleNotification(NotificationListener listener, Notification notif, Object handback)`	This method is called by `sendNotification` for each listener in order to send the notification to that listener.
`void`	`removeNotificationListener(NotificationListener listener)`	Removes a listener from this MBean.
`void`	`removeNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback)`	Removes a listener from this MBean.
`void`	`sendNotification(Notification notification)`	Sends a notification.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this 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 it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

StringMonitor

public StringMonitor()

Default constructor.

Method Details

start

public void start()

Starts the string monitor.

Specified by:: start in interface MonitorMBean
Specified by:: start in class Monitor

stop

public void stop()

Stops the string monitor.

Specified by:: stop in interface MonitorMBean
Specified by:: stop in class Monitor

getDerivedGauge

public String 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.

Specified by:: getDerivedGauge in interface StringMonitorMBean
Parameters:: object - the name of the MBean whose derived gauge is required.
Returns:: The derived gauge of the specified object.

getDerivedGaugeTimeStamp

public 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.

Specified by:: getDerivedGaugeTimeStamp in interface StringMonitorMBean
Parameters:: object - the name of the object whose derived gauge timestamp is to be returned.
Returns:: The derived gauge timestamp of the specified object.

getDerivedGauge

@Deprecated public String getDerivedGauge()

Deprecated.

As of JMX 1.2, replaced by getDerivedGauge(ObjectName)

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

Specified by:: getDerivedGauge in interface StringMonitorMBean
Returns:: The derived gauge.

getDerivedGaugeTimeStamp

@Deprecated public long getDerivedGaugeTimeStamp()

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.

Specified by:: getDerivedGaugeTimeStamp in interface StringMonitorMBean
Returns:: The derived gauge timestamp.

getStringToCompare

public String getStringToCompare()

Gets the string to compare with the observed attribute common to all observed MBeans.

Specified by:

getStringToCompare in interface StringMonitorMBean

Returns:

The string value.

See Also:

setStringToCompare

public void setStringToCompare(String value) throws IllegalArgumentException

Sets the string to compare with the observed attribute common to all observed MBeans.

Specified by:

setStringToCompare in interface StringMonitorMBean

Parameters:

value - The string value.

Throws:

IllegalArgumentException - The specified string to compare is null.

See Also:

getNotifyMatch

public boolean getNotifyMatch()

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

Specified by:

getNotifyMatch in interface StringMonitorMBean

Returns:

true if the string monitor notifies when matching the string to compare, false otherwise.

See Also:

setNotifyMatch

public void setNotifyMatch(boolean value)

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

Specified by:

setNotifyMatch in interface StringMonitorMBean

Parameters:

value - The matching notification's on/off switch value.

See Also:

getNotifyDiffer

public boolean getNotifyDiffer()

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

Specified by:

getNotifyDiffer in interface StringMonitorMBean

Returns:

true if the string monitor notifies when differing from the string to compare, false otherwise.

See Also:

setNotifyDiffer

public void setNotifyDiffer(boolean value)

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

Specified by:

setNotifyDiffer in interface StringMonitorMBean

Parameters:

value - The differing notification's on/off switch value.

See Also:

getNotificationInfo

public MBeanNotificationInfo[] getNotificationInfo()

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

Specified by:: getNotificationInfo in interface NotificationBroadcaster
Returns:: the array of possible notifications.

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