Class Monitor
- java.lang.Object
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- javax.management.NotificationBroadcasterSupport
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- javax.management.monitor.Monitor
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- All Implemented Interfaces:
- MBeanRegistration, MonitorMBean, NotificationBroadcaster, NotificationEmitter
- Direct Known Subclasses:
- CounterMonitor, GaugeMonitor, StringMonitor
public abstract class Monitor extends NotificationBroadcasterSupport implements MonitorMBean, MBeanRegistration
Defines the part common to all monitor MBeans. A monitor MBean monitors values of an attribute common to a set of observed MBeans. The observed attribute is monitored at intervals specified by the granularity period. A gauge value (derived gauge) is derived from the values of the observed attribute.- Since:
- 1.5
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Field Summary
Fields Modifier and Type Field and Description protected int
alreadyNotified
Deprecated.equivalent toalreadyNotifieds
[0].protected int[]
alreadyNotifieds
Selected monitor errors that have already been notified.protected static 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 int
OBSERVED_ATTRIBUTE_ERROR_NOTIFIED
Flag denoting that a notification has occurred after changing the observed attribute.protected static int
OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED
Flag denoting that a notification has occurred after changing the observed object or the observed attribute.protected static int
OBSERVED_OBJECT_ERROR_NOTIFIED
Flag denoting that a notification has occurred after changing the observed object.protected static int
RESET_FLAGS_ALREADY_NOTIFIED
This flag is used to reset thealreadyNotifieds
monitor attribute.protected static 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.
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Constructor Summary
Constructors Constructor and Description Monitor()
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Method Summary
All Methods Instance Methods Abstract Methods Concrete Methods Deprecated Methods Modifier and Type Method and 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 bygetObservedObjects()
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 byaddObservedObject(javax.management.ObjectName)
abstract void
start()
Starts the monitor.abstract void
stop()
Stops the monitor.-
Methods inherited from class javax.management.NotificationBroadcasterSupport
addNotificationListener, getNotificationInfo, handleNotification, removeNotificationListener, removeNotificationListener, sendNotification
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Field Detail
capacityIncrement
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.- See Also:
- Constant Field Values
elementCount
protected int elementCount
The number of valid components in the vector of observed objects.
alreadyNotified
@Deprecated protected int alreadyNotified
Deprecated. equivalent toalreadyNotifieds
[0].Monitor errors that have already been notified.
alreadyNotifieds
protected int[] alreadyNotifieds
Selected monitor errors that have already been notified.
Each element in this array corresponds to an observed object in the vector. It contains a bit mask of the flags
OBSERVED_OBJECT_ERROR_NOTIFIED
etc, indicating whether the corresponding notification has already been sent for the MBean being monitored.
server
protected MBeanServer server
Reference to the MBean server. This reference is null when the monitor MBean is not registered in an MBean server. This reference is initialized before the monitor MBean is registered in the MBean server.
RESET_FLAGS_ALREADY_NOTIFIED
protected static final int RESET_FLAGS_ALREADY_NOTIFIED
This flag is used to reset thealreadyNotifieds
monitor attribute.- See Also:
- Constant Field Values
OBSERVED_OBJECT_ERROR_NOTIFIED
protected static final int OBSERVED_OBJECT_ERROR_NOTIFIED
Flag denoting that a notification has occurred after changing the observed object. This flag is used to check that the new observed object is registered in the MBean server at the time of the first notification.- See Also:
- Constant Field Values
OBSERVED_ATTRIBUTE_ERROR_NOTIFIED
protected static final int OBSERVED_ATTRIBUTE_ERROR_NOTIFIED
Flag denoting that a notification has occurred after changing the observed attribute. This flag is used to check that the new observed attribute belongs to the observed object at the time of the first notification.- See Also:
- Constant Field Values
OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED
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. This flag is used to check that the observed attribute type is correct (depending on the monitor in use) at the time of the first notification.- See Also:
- Constant Field Values
RUNTIME_ERROR_NOTIFIED
protected static final int RUNTIME_ERROR_NOTIFIED
Flag denoting that a notification has occurred after changing the observed object or the observed attribute. This flag is used to notify any exception (except the cases described above) when trying to get the value of the observed attribute at the time of the first notification.- See Also:
- Constant Field Values
dbgTag
@Deprecated protected String dbgTag
Deprecated. No replacement.This field is retained for compatibility but should not be referenced.
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Method Detail
preRegister
public ObjectName preRegister(MBeanServer server, ObjectName name) throws Exception
Allows the monitor MBean to perform any operations it needs before being registered in the MBean server.Initializes the reference to the MBean server.
- Specified by:
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preRegister
in interfaceMBeanRegistration
- Parameters:
-
server
- The MBean server in which the monitor MBean will be registered. -
name
- The object name of the monitor MBean. - Returns:
- The name of the monitor MBean registered.
- Throws:
-
Exception
postRegister
public 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.Not used in this context.
- Specified by:
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postRegister
in interfaceMBeanRegistration
- Parameters:
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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 monitor MBean to perform any operations it needs before being unregistered by the MBean server.Stops the monitor.
- Specified by:
-
preDeregister
in interfaceMBeanRegistration
- Throws:
-
Exception
postDeregister
public void postDeregister()
Allows the monitor MBean to perform any operations needed after having been unregistered by the MBean server.Not used in this context.
- Specified by:
-
postDeregister
in interfaceMBeanRegistration
start
public abstract void start()
Starts the monitor.- Specified by:
-
start
in interfaceMonitorMBean
stop
public abstract void stop()
Stops the monitor.- Specified by:
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stop
in interfaceMonitorMBean
getObservedObject
@Deprecated public ObjectName getObservedObject()
Deprecated. As of JMX 1.2, replaced bygetObservedObjects()
Returns the object name of the first object in the set of observed MBeans, ornull
if there is no such object.- Specified by:
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getObservedObject
in interfaceMonitorMBean
- Returns:
- The object being observed.
- See Also:
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setObservedObject(ObjectName)
setObservedObject
@Deprecated public void setObservedObject(ObjectName object) throws IllegalArgumentException
Deprecated. As of JMX 1.2, replaced byaddObservedObject(javax.management.ObjectName)
Removes all objects from the set of observed objects, and then adds the specified object.- Specified by:
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setObservedObject
in interfaceMonitorMBean
- Parameters:
-
object
- The object to observe. - Throws:
-
IllegalArgumentException
- The specified object is null. - See Also:
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getObservedObject()
addObservedObject
public void addObservedObject(ObjectName object) throws IllegalArgumentException
Adds the specified object in the set of observed MBeans, if this object is not already present.- Specified by:
-
addObservedObject
in interfaceMonitorMBean
- Parameters:
-
object
- The object to observe. - Throws:
-
IllegalArgumentException
- The specified object is null.
removeObservedObject
public void removeObservedObject(ObjectName object)
Removes the specified object from the set of observed MBeans.- Specified by:
-
removeObservedObject
in interfaceMonitorMBean
- Parameters:
-
object
- The object to remove.
containsObservedObject
public boolean containsObservedObject(ObjectName object)
Tests whether the specified object is in the set of observed MBeans.- Specified by:
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containsObservedObject
in interfaceMonitorMBean
- Parameters:
-
object
- The object to check. - Returns:
-
true
if the specified object is present,false
otherwise.
getObservedObjects
public ObjectName[] getObservedObjects()
Returns an array containing the objects being observed.- Specified by:
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getObservedObjects
in interfaceMonitorMBean
- Returns:
- The objects being observed.
getObservedAttribute
public String getObservedAttribute()
Gets the attribute being observed.
The observed attribute is not initialized by default (set to null).- Specified by:
-
getObservedAttribute
in interfaceMonitorMBean
- Returns:
- The attribute being observed.
- See Also:
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setObservedAttribute(java.lang.String)
setObservedAttribute
public void setObservedAttribute(String attribute) throws IllegalArgumentException
Sets the attribute to observe.
The observed attribute is not initialized by default (set to null).- Specified by:
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setObservedAttribute
in interfaceMonitorMBean
- Parameters:
-
attribute
- The attribute to observe. - Throws:
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IllegalArgumentException
- The specified attribute is null. - See Also:
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getObservedAttribute()
getGranularityPeriod
public long getGranularityPeriod()
Gets the granularity period (in milliseconds).
The default value of the granularity period is 10 seconds.- Specified by:
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getGranularityPeriod
in interfaceMonitorMBean
- Returns:
- The granularity period value.
- See Also:
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setGranularityPeriod(long)
setGranularityPeriod
public void setGranularityPeriod(long period) throws IllegalArgumentException
Sets the granularity period (in milliseconds).
The default value of the granularity period is 10 seconds.- Specified by:
-
setGranularityPeriod
in interfaceMonitorMBean
- Parameters:
-
period
- The granularity period value. - Throws:
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IllegalArgumentException
- The granularity period is less than or equal to zero. - See Also:
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getGranularityPeriod()
isActive
public boolean isActive()
Tests whether the monitor MBean is active. A monitor MBean is marked active when thestart
method is called. It becomes inactive when thestop
method is called.- Specified by:
-
isActive
in interfaceMonitorMBean
- Returns:
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true
if the monitor MBean is active,false
otherwise.
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