Module org.tquadrat.foundation.mgmt

Package org.tquadrat.foundation.mgmt.internal

Class JMXSupportImpl<T>

java.lang.Object

org.tquadrat.foundation.mgmt.internal.JMXSupportImpl<T>

Type Parameters:

T - The type of the managed object.

All Implemented Interfaces:

DynamicMBean, NotificationBroadcaster, NotificationEmitter, JMXSupport<T>

@ClassVersion(sourceVersion="$Id: JMXSupportImpl.java 1070 2023-09-29 17:09:34Z tquadrat $")
@API(status=INTERNAL,
     since="0.0.1")
public final class JMXSupportImpl<T>
extends Object
implements JMXSupport<T>

This class implements the interface JMXSupport that in turn extends the definition for a dynamic MBean (DynamicMBean) and can instrument any object whose class is annotated properly.

Author:

Thomas Thrien (thomas.thrien@tquadrat.org)

Version:

$Id: JMXSupportImpl.java 1070 2023-09-29 17:09:34Z tquadrat $

Since:

0.0.1

See Also:

• ManagedObject
• MBeanAction
• MBeanGetter
• MBeanNotification
• MBeanNotifications
• MBeanSetter

UML Diagram

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UML Diagram for "org.tquadrat.foundation.mgmt.internal.JMXSupportImpl"

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Field Summary

Fields

Modifier and Type	Field	Description
private Optional<NotificationBroadcasterSupport>	m_BroadcasterSupport	This object supports the broadcasting of notifications.
private final Map<String,Method>	m_MBeanActions	The actions (operations) for the JMX API; the action name is the key for this map.
private final Map<String,Method>	m_MBeanGetters	The getters for the JMX API; the attribute name is the key for this map.
private final Lazy<MBeanInfo>	m_MBeanInfo	The predefined MBeanInfo structure.
private final Map<String,Method>	m_MBeanSetters	The setters for the JMX API; the attribute name is the key for this map.
private final T	m_Object	The object that is instrumented by this generic MBean.
private final String	m_ObjectDescription	The description for the object that is instrumented by this generic MBean.
private final ObjectName	m_ObjectName	The object name for this generic MBean.
private final AtomicLong	m_Sequence	The notification sequence number.
static final String	MSG_ActionNotFound	Message: "There is no MBean action with the name \'%1$s\'".
static final String	MSG_AttributeNotFound	Message: "The MBean attribute \'%1$s\' could not be found".
static final String	MSG_InvalidAttributeValue	Message: "The value \'%2$s\' is invalid for the MBean attribute with the name \'%1$s\'".
static final String	MSG_InvocationDenied	Message: "Cannot invoke the MBean action \'%1$s\'".
static final String	MSG_InvocationException	Message: "The invocation of the MBean action \'%1$s\' caused an Exception".
static final String	MSG_InvocationProblems	Message: "There was a problem when invoking the MBean action \'%1$s\'".
static final String	MSG_NoManagedObject	Message: "The given Object is not annotated as \'ManagedObject\'".
static final String	MSG_NoProperties	Message: "No properties had been provided".
static final String	MSG_SetterDenied	Message: "The invocation of the setter for the MBean attribute \'%1$s\' was denied".
static final String	MSG_SetterException	Message: "The invocation of the setter for the MBean attribute \'%1$s\' caused an Exception".
static final String	MSG_SetterProblems	Message: "There was a problem when invoking the setter for the MBean attribute \'%1$s\'".

Constructor Summary

Constructors

Modifier	Constructor	Description
private	JMXSupportImpl(T object, ObjectName name, String description, boolean useNotifications, ThreadFactory threadFactory)	Initialises the abstract server part of a concrete server implementation.

Method Summary

Modifier and Type	Method	Description
final void	addNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback)
private final MBeanOperationInfo[]	createActionInfo()	Creates the structure that holds the action information.
private final MBeanAttributeInfo[]	createAttributeInfo()	Creates the structure that holds the attribute information.
private MBeanInfo	createMBeanInfo()	Creates the MBeanInfo data structure. This implementation will swallow all exceptions, an overriding implementation may want to log it.
private MBeanNotificationInfo[]	createNotificationInfo(Object object)	Creates the structure that holds the notification info.
private static MBeanNotificationInfo	createNotificationInfo(MBeanNotification notification)	Creates a single notification info element.
private static MBeanParameterInfo[]	determineSignature(Method method)	Determines the parameter information for the given method.
final Object	getAttribute(String attributeName)
AttributeList	getAttributes(String[] attributes)	Get the values of several attributes of the Dynamic MBean.
final MBeanInfo	getMBeanInfo()
final long	getNextNotificationSequenceNumber()	Returns the sequence number that is used for the next notification.
final MBeanNotificationInfo[]	getNotificationInfo()
final T	getObject()	Returns the object that is instrumented by this MBean instance.
final String	getObjectDescription()	Returns the object description.
final ObjectName	getObjectName()	Returns the object name for this MBean.
final Object	invoke(String actionName, Object[] params, String[] signature)
static <O> JMXSupport<O>	register(O object, ObjectName objectName, ThreadFactory threadFactory)	Registers the server with the JMX agent.
private static void	registerMBean(DynamicMBean mbean, ObjectName objectName)	Register the MBean with the platform MBeanServer.
final void	removeNotificationListener(NotificationListener listener)
final void	removeNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback)
private long	retrieveNextNotificationSequenceNumber()	Returns the notification sequence number for the current notification and increments the number.
final <A, V extends A> void	sendAttributeChangeNotification(String message, String description, Class<A> attributeType, V oldValue, V newValue)	Sends an attribute change notification.
final void	sendNotification(String type, String message)	Sends a simple notification with a message text.
private final void	sendNotification(Notification notification)	Sends a notification.
final void	setAttribute(Attribute attribute)	Sets the value of a specific attribute of the generic MBean.
AttributeList	setAttributes(AttributeList attributes)	Sets the values of several attributes of the generic MBean.
final void	unregister()	Unregisters the MBean from the MBeanServer.

Methods inherited from class java.lang.Object

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

Field Details

MSG_ActionNotFound

public static final String MSG_ActionNotFound

Message: "There is no MBean action with the name \'%1$s\'".

See Also:

• Constant Field Values

MSG_AttributeNotFound

public static final String MSG_AttributeNotFound

Message: "The MBean attribute \'%1$s\' could not be found".

See Also:

• Constant Field Values

MSG_InvalidAttributeValue

public static final String MSG_InvalidAttributeValue

Message: "The value \'%2$s\' is invalid for the MBean attribute with the name \'%1$s\'".

See Also:

• Constant Field Values

MSG_InvocationDenied

public static final String MSG_InvocationDenied

Message: "Cannot invoke the MBean action \'%1$s\'".

See Also:

• Constant Field Values

MSG_InvocationException

public static final String MSG_InvocationException

Message: "The invocation of the MBean action \'%1$s\' caused an Exception".

See Also:

• Constant Field Values

MSG_InvocationProblems

public static final String MSG_InvocationProblems

Message: "There was a problem when invoking the MBean action \'%1$s\'".

See Also:

• Constant Field Values

MSG_NoManagedObject

public static final String MSG_NoManagedObject

Message: "The given Object is not annotated as \'ManagedObject\'".

See Also:

• Constant Field Values

MSG_NoProperties

public static final String MSG_NoProperties

Message: "No properties had been provided".

See Also:

• Constant Field Values

MSG_SetterDenied

public static final String MSG_SetterDenied

Message: "The invocation of the setter for the MBean attribute \'%1$s\' was denied".

See Also:

• Constant Field Values

MSG_SetterException

public static final String MSG_SetterException

Message: "The invocation of the setter for the MBean attribute \'%1$s\' caused an Exception".

See Also:

• Constant Field Values

MSG_SetterProblems

public static final String MSG_SetterProblems

Message: "There was a problem when invoking the setter for the MBean attribute \'%1$s\'".

See Also:

• Constant Field Values

m_BroadcasterSupport

private Optional<NotificationBroadcasterSupport> m_BroadcasterSupport

This object supports the broadcasting of notifications. It is Optional.empty() if the object, that is instrumented by this instance of JMXSupport, indicates in its ManagedObject annotation that it will not use notifications.

m_MBeanActions

private final Map<String,Method> m_MBeanActions

The actions (operations) for the JMX API; the action name is the key for this map.

m_MBeanGetters

private final Map<String,Method> m_MBeanGetters

The getters for the JMX API; the attribute name is the key for this map.

m_MBeanInfo

private final Lazy<MBeanInfo> m_MBeanInfo

The predefined MBeanInfo structure.

m_MBeanSetters

private final Map<String,Method> m_MBeanSetters

The setters for the JMX API; the attribute name is the key for this map.

m_Object

private final T m_Object

The object that is instrumented by this generic MBean.

m_ObjectDescription

private final String m_ObjectDescription

The description for the object that is instrumented by this generic MBean.

m_ObjectName

private final ObjectName m_ObjectName

The object name for this generic MBean.

m_Sequence

private final AtomicLong m_Sequence

The notification sequence number.

Constructor Details

JMXSupportImpl

private JMXSupportImpl(T object,
 ObjectName name,
 String description,
 boolean useNotifications,
 ThreadFactory threadFactory)

Initialises the abstract server part of a concrete server implementation.

Parameters:

object - The object to register with the JMX agent.

name - The object name for the MBean.

description - The description for the MBean.

useNotifications - true if the instrumented object will send notifications, false (the default) otherwise.

threadFactory - The thread factory that is used when notifications will be emitted asynchronously; can be null and will be ignored if useNotifications is false.

Method Details

addNotificationListener

public final void addNotificationListener(NotificationListener listener,
 NotificationFilter filter,
 Object handback)

Specified by:

addNotificationListener in interface NotificationBroadcaster

createActionInfo

private final MBeanOperationInfo[] createActionInfo()

Creates the structure that holds the action information.

Returns:

The action (or operation) information.

createAttributeInfo

private final MBeanAttributeInfo[] createAttributeInfo()
                                                throws IntrospectionException

Creates the structure that holds the attribute information.

Returns:

The attribute information.

Throws:

IntrospectionException - There is a consistency problem in the definition of an attribute.

createMBeanInfo

private MBeanInfo createMBeanInfo()

Creates the MBeanInfo data structure.

This implementation will swallow all exceptions, an overriding implementation may want to log it.

Returns:

An instance of MBeanInfo allowing all attributes and actions exposed by this generic MBean to be retrieved.

createNotificationInfo

private static MBeanNotificationInfo createNotificationInfo(MBeanNotification notification)

Creates a single notification info element.

Parameters:

notification - The annotation data.

Returns:

The notification info element.

createNotificationInfo

private MBeanNotificationInfo[] createNotificationInfo(Object object)

Creates the structure that holds the notification info.

Parameters:

object - The object to examine.

Returns:

The notification info structure.

determineSignature

private static MBeanParameterInfo[] determineSignature(Method method)

Determines the parameter information for the given method.

Parameters:

method - The method to analyse.

Returns:

The parameter info structure.

getAttribute

public final Object getAttribute(String attributeName)
                          throws AttributeNotFoundException,
MBeanException,
ReflectionException

Specified by:

getAttribute in interface DynamicMBean

Throws:

AttributeNotFoundException

MBeanException

ReflectionException

getAttributes

public AttributeList getAttributes(String[] attributes)

Get the values of several attributes of the Dynamic MBean. This implementation will swallow all exceptions that might be thrown.

Specified by:

getAttributes in interface DynamicMBean

Parameters:

attributes - A list of the attributes to be retrieved.

Returns:

The list of attributes retrieved.

getMBeanInfo

public final MBeanInfo getMBeanInfo()

Specified by:

getMBeanInfo in interface DynamicMBean

getNextNotificationSequenceNumber

public final long getNextNotificationSequenceNumber()

Returns the sequence number that is used for the next notification.

Specified by:

getNextNotificationSequenceNumber in interface JMXSupport<T>

Returns:

The next sequence number.

getNotificationInfo

public final MBeanNotificationInfo[] getNotificationInfo()

Specified by:

getNotificationInfo in interface NotificationBroadcaster

getObject

public final T getObject()

Returns the object that is instrumented by this MBean instance.

Specified by:

getObject in interface JMXSupport<T>

Returns:

The instrumented object.

getObjectDescription

public final String getObjectDescription()

Returns the object description.

Specified by:

getObjectDescription in interface JMXSupport<T>

Returns:

The object description.

getObjectName

public final ObjectName getObjectName()

Returns the object name for this MBean. This is a copy of that instance that is used during registration, not the real thing. Therefore, it should be only used for reference.

Specified by:

getObjectName in interface JMXSupport<T>

Returns:

A copy of the MBean's object name.

invoke

public final Object invoke(String actionName,
 Object[] params,
 String[] signature)
                    throws MBeanException,
ReflectionException

Specified by:

invoke in interface DynamicMBean

Throws:

MBeanException

ReflectionException

removeNotificationListener

public final void removeNotificationListener(NotificationListener listener)
                                      throws ListenerNotFoundException

Specified by:

removeNotificationListener in interface NotificationBroadcaster

Throws:

ListenerNotFoundException

removeNotificationListener

public final void removeNotificationListener(NotificationListener listener,
 NotificationFilter filter,
 Object handback)
                                      throws ListenerNotFoundException

Specified by:

removeNotificationListener in interface NotificationEmitter

Throws:

ListenerNotFoundException

register

public static <O> JMXSupport<O> register(O object,
 ObjectName objectName,
 ThreadFactory threadFactory)
                                  throws IllegalArgumentException,
InstanceAlreadyExistsException,
MBeanRegistrationException

Registers the server with the JMX agent.

Type Parameters:

O - The type of the object.

Parameters:

object - The object to register with the JMX agent.

objectName - The object name that is used for the object to register.

threadFactory - The thread factory that is used when notifications should be sent asynchronously; can be null.

Returns:

The MBean object that was generated as the instrumentation for the object to manage.

Throws:

IllegalArgumentException - The object is not annotated with @ManagedObject.

InstanceAlreadyExistsException - There is already a MBean with the given object name registered.

MBeanRegistrationException - Problems with the registration of the MBean.

registerMBean

private static void registerMBean(DynamicMBean mbean,
 ObjectName objectName)
                           throws InstanceAlreadyExistsException,
MBeanRegistrationException

Register the MBean with the platform MBeanServer.

Parameters:

mbean - The MBean to register.

objectName - The object name for the registration.

Throws:

InstanceAlreadyExistsException - There is already an MBean with the given object name.

MBeanRegistrationException - Problems with the registration of the MBean.

retrieveNextNotificationSequenceNumber

private long retrieveNextNotificationSequenceNumber()

Returns the notification sequence number for the current notification and increments the number.

Returns:

The next sequence number.

sendAttributeChangeNotification

public final <A,
V extends A> void sendAttributeChangeNotification(String message,
 String description,
 Class<A> attributeType,
 V oldValue,
 V newValue)

Sends an attribute change notification. The type is always jmx.attribute.change.

Specified by:

sendAttributeChangeNotification in interface JMXSupport<T>

Type Parameters:

A - The type for the attribute.

V - The type for the values.

Parameters:

message - The message for this notification.

description - The description for the attribute.

attributeType - The type of the attribute.

oldValue - The old value.

newValue - The new value.

sendNotification

private final void sendNotification(Notification notification)

Sends a notification. It is not recommended using this method directly as this class will provide some very helpful convenience methods.

If it is really necessary to create your own implementation for a notification, it is important that the source element is set to a reference to this instance, and not to the object that is instrumented using this object.

Parameters:

notification - The notification to send.

See Also:

• NotificationBroadcasterSupport.sendNotification(javax.management.Notification)
• Notification.setSource(Object)
• EventObject.getSource()

sendNotification

public final void sendNotification(String type,
 String message)

Sends a simple notification with a message text.

Specified by:

sendNotification in interface JMXSupport<T>

Parameters:

type - The type of the notification.

message - The message for this notification.

setAttribute

public final void setAttribute(Attribute attribute)
                        throws AttributeNotFoundException,
InvalidAttributeValueException,
MBeanException,
ReflectionException

Sets the value of a specific attribute of the generic MBean.

Specified by:

setAttribute in interface DynamicMBean

Parameters:

attribute - The identification of the attribute to be set and the value it is to be set to.

Throws:

AttributeNotFoundException - There is no attribute with the given name.

InvalidAttributeValueException - The value of the attribute does not fit to the attribute's declaration.

MBeanException - Wraps a Exception thrown by the MBean's setter.

ReflectionException - Wraps a Exception thrown while trying to invoke MBean's setter.

See Also:

• getAttribute()
• DynamicMBean.setAttribute(javax.management.Attribute)

setAttributes

public AttributeList setAttributes(AttributeList attributes)

Sets the values of several attributes of the generic MBean. This implementation will silently swallow any exception that might occur; an implementation in a subclass might want to log them.

An Attribute that causes an exception when setAttribute() is called with it will not be part of the returned list of attributes.

Specified by:

setAttributes in interface DynamicMBean

Parameters:

attributes - A list of attributes: The identification of the attributes to be set and the values they are to be set to.

Returns:

The list of attributes that were set, with their new values.

See Also:

• getAttributes()
• DynamicMBean.setAttributes(javax.management.AttributeList)

unregister

public final void unregister()
                      throws InstanceNotFoundException,
MBeanRegistrationException

Unregisters the MBean from the MBeanServer.

Specified by:

unregister in interface JMXSupport<T>

Throws:

InstanceNotFoundException - The MBean is not registered.

MBeanRegistrationException - Problems with the registration of the MBean.