Class RequiredModelMBean

public RequiredModelMBean() throws MBeanException, RuntimeOperationsException

Constructs an RequiredModelMBean with an empty ModelMBeanInfo.

The RequiredModelMBean's MBeanInfo and Descriptors can be customized using the setModelMBeanInfo(javax.management.modelmbean.ModelMBeanInfo) method. After the RequiredModelMBean's MBeanInfo and Descriptors are customized, the RequiredModelMBean can be registered with the MBeanServer.

public RequiredModelMBean(ModelMBeanInfo mbi) throws MBeanException, RuntimeOperationsException

Constructs a RequiredModelMBean object using ModelMBeanInfo passed in. As long as the RequiredModelMBean is not registered with the MBeanServer yet, the RequiredModelMBean's MBeanInfo and Descriptors can be customized using the setModelMBeanInfo(javax.management.modelmbean.ModelMBeanInfo) method. After the RequiredModelMBean's MBeanInfo and Descriptors are customized, the RequiredModelMBean can be registered with the MBeanServer.

public void setModelMBeanInfo(ModelMBeanInfo mbi) throws MBeanException, RuntimeOperationsException

Initializes a ModelMBean object using ModelMBeanInfo passed in. This method makes it possible to set a customized ModelMBeanInfo on the ModelMBean as long as it is not registered with the MBeanServer.
Once the ModelMBean's ModelMBeanInfo (with Descriptors) are customized and set on the ModelMBean, the ModelMBean be registered with the MBeanServer.

If the ModelMBean is currently registered, this method throws a RuntimeOperationsException wrapping an IllegalStateException

If the given inModelMBeanInfo does not contain any ModelMBeanNotificationInfo for the GENERIC or ATTRIBUTE_CHANGE notifications, then the RequiredModelMBean will supply its own default ModelMBeanNotificationInfos for those missing notifications.

public void setManagedResource(Object mr, String mr_type) throws MBeanException, RuntimeOperationsException, InstanceNotFoundException, InvalidTargetObjectTypeException

Sets the instance handle of the object against which to execute all methods in this ModelMBean management interface (MBeanInfo and Descriptors).

public void load() throws MBeanException, RuntimeOperationsException, InstanceNotFoundException

Instantiates this MBean instance with the data found for the MBean in the persistent store. The data loaded could include attribute and operation values.

This method should be called during construction or initialization of this instance, and before the MBean is registered with the MBeanServer.

If the implementation of this class does not support persistence, an MBeanException wrapping a ServiceNotFoundException is thrown.

public void store() throws MBeanException, RuntimeOperationsException, InstanceNotFoundException

Captures the current state of this MBean instance and writes it out to the persistent store. The state stored could include attribute and operation values.

If the implementation of this class does not support persistence, an MBeanException wrapping a ServiceNotFoundException is thrown.

Persistence policy from the MBean and attribute descriptor is used to guide execution of this method. The MBean should be stored if 'persistPolicy' field is:

 != "never"
   = "always"
   = "onTimer" and now > 'lastPersistTime' + 'persistPeriod'
   = "NoMoreOftenThan" and now > 'lastPersistTime' + 'persistPeriod'
   = "onUnregister"
 

Do not store the MBean if 'persistPolicy' field is:

    = "never"
    = "onUpdate"
    = "onTimer" && now < 'lastPersistTime' + 'persistPeriod'
 

public MBeanInfo getMBeanInfo()

Returns the attributes, operations, constructors and notifications that this RequiredModelMBean exposes for management.

public Object invoke(String opName, Object[] opArgs, String[] sig) throws MBeanException, ReflectionException

Invokes a method on or through a RequiredModelMBean and returns the result of the method execution.

If the given method to be invoked, together with the provided signature, matches one of RequiredModelMbean accessible methods, this one will be call. Otherwise the call to the given method will be tried on the managed resource.

The last value returned by an operation may be cached in the operation's descriptor which is in the ModelMBeanOperationInfo's descriptor. The valid value will be in the 'value' field if there is one. If the 'currencyTimeLimit' field in the descriptor is:

• <0 Then the value is not cached and is never valid. The operation method is invoked. The 'value' and 'lastUpdatedTimeStamp' fields are cleared.
• =0 Then the value is always cached and always valid. The 'value' field is returned. If there is no 'value' field then the operation method is invoked for the attribute. The 'lastUpdatedTimeStamp' field and `value' fields are set to the operation's return value and the current time stamp.
• >0 Represents the number of seconds that the 'value' field is valid. The 'value' field is no longer valid when 'lastUpdatedTimeStamp' + 'currencyTimeLimit' > Now.
  • When 'value' is valid, 'value' is returned.
  • When 'value' is no longer valid then the operation method is invoked. The 'lastUpdatedTimeStamp' field and `value' fields are updated.

Note: because of inconsistencies in previous versions of this specification, it is recommended not to use negative or zero values for currencyTimeLimit. To indicate that a cached value is never valid, omit the currencyTimeLimit field. To indicate that it is always valid, use a very large number for this field.

public Object getAttribute(String attrName) throws AttributeNotFoundException, MBeanException, ReflectionException

Returns the value of a specific attribute defined for this ModelMBean. The last value returned by an attribute may be cached in the attribute's descriptor. The valid value will be in the 'value' field if there is one. If the 'currencyTimeLimit' field in the descriptor is:

• <0 Then the value is not cached and is never valid. The getter method is invoked for the attribute. The 'value' and 'lastUpdatedTimeStamp' fields are cleared.
• =0 Then the value is always cached and always valid. The 'value' field is returned. If there is no'value' field then the getter method is invoked for the attribute. The 'lastUpdatedTimeStamp' field and `value' fields are set to the attribute's value and the current time stamp.
• >0 Represents the number of seconds that the 'value' field is valid. The 'value' field is no longer valid when 'lastUpdatedTimeStamp' + 'currencyTimeLimit' > Now.
  • When 'value' is valid, 'value' is returned.
  • When 'value' is no longer valid then the getter method is invoked for the attribute. The 'lastUpdatedTimeStamp' field and `value' fields are updated.

Note: because of inconsistencies in previous versions of this specification, it is recommended not to use negative or zero values for currencyTimeLimit. To indicate that a cached value is never valid, omit the currencyTimeLimit field. To indicate that it is always valid, use a very large number for this field.

If the 'getMethod' field contains the name of a valid operation descriptor, then the method described by the operation descriptor is executed. The response from the method is returned as the value of the attribute. If the operation fails or the returned value is not compatible with the declared type of the attribute, an exception will be thrown.

If no 'getMethod' field is defined then the default value of the attribute is returned. If the returned value is not compatible with the declared type of the attribute, an exception will be thrown.

The declared type of the attribute is the String returned by MBeanAttributeInfo.getType(). A value is compatible with this type if one of the following is true:

• the value is null;
• the declared name is a primitive type name (such as "int") and the value is an instance of the corresponding wrapper type (such as java.lang.Integer);
• the name of the value's class is identical to the declared name;
• the declared name can be loaded by the value's class loader and produces a class to which the value can be assigned.

In this implementation, in every case where the getMethod needs to be called, because the method is invoked through the standard "invoke" method and thus needs operationInfo, an operation must be specified for that getMethod so that the invocation works correctly.

public AttributeList getAttributes(String[] attrNames)

Returns the values of several attributes in the ModelMBean. Executes a getAttribute for each attribute name in the attrNames array passed in.

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

Sets the value of a specific attribute of a named ModelMBean. If the 'setMethod' field of the attribute's descriptor contains the name of a valid operation descriptor, then the method described by the operation descriptor is executed. In this implementation, the operation descriptor must be specified correctly and assigned to the modelMBeanInfo so that the 'setMethod' works correctly. The response from the method is set as the value of the attribute in the descriptor.

If currencyTimeLimit is > 0, then the new value for the attribute is cached in the attribute descriptor's 'value' field and the 'lastUpdatedTimeStamp' field is set to the current time stamp.

If the persist field of the attribute's descriptor is not null then Persistence policy from the attribute descriptor is used to guide storing the attribute in a persistent store.
Store the MBean if 'persistPolicy' field is:

• != "never"
• = "always"
• = "onUpdate"
• = "onTimer" and now > 'lastPersistTime' + 'persistPeriod'
• = "NoMoreOftenThan" and now > 'lastPersistTime' + 'persistPeriod'

Do not store the MBean if 'persistPolicy' field is:

• = "never"
• = = "onTimer" && now < 'lastPersistTime' + 'persistPeriod'
• = "onUnregister"
• = = "NoMoreOftenThan" and now < 'lastPersistTime' + 'persistPeriod'

The ModelMBeanInfo of the Model MBean is stored in a file.

public AttributeList setAttributes(AttributeList attributes)

Sets the values of an array of attributes of this ModelMBean. Executes the setAttribute() method for each attribute in the list.

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

Registers an object which implements the NotificationListener interface as a listener. This object's 'handleNotification()' method will be invoked when any notification is issued through or by the ModelMBean. This does not include attributeChangeNotifications. They must be registered for independently.

public void removeNotificationListener(NotificationListener listener) throws ListenerNotFoundException

Removes a listener for Notifications from the RequiredModelMBean.

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

Removes a listener from this MBean. The MBean must have a listener that exactly matches the given listener, filter, and handback parameters. If there is more than one such listener, only one is removed.

The filter and handback parameters may be null if and only if they are null in a listener to be removed.

public void sendNotification(Notification ntfyObj) throws MBeanException, RuntimeOperationsException

Sends a Notification which is passed in to the registered Notification listeners on the ModelMBean as a jmx.modelmbean.generic notification.

public void sendNotification(String ntfyText) throws MBeanException, RuntimeOperationsException

Sends a Notification which contains the text string that is passed in to the registered Notification listeners on the ModelMBean.

public MBeanNotificationInfo[] getNotificationInfo()

Returns the array of Notifications always generated by the RequiredModelMBean.

RequiredModelMBean may always send also two additional notifications:

• One with descriptor "name=GENERIC,descriptorType=notification,log=T,severity=6,displayName=jmx.modelmbean.generic"
• Second is a standard attribute change notification with descriptor "name=ATTRIBUTE_CHANGE,descriptorType=notification,log=T,severity=6,displayName=jmx.attribute.change"

Thus these two notifications are always added to those specified by the application.

public void addAttributeChangeNotificationListener(NotificationListener inlistener, String inAttributeName, Object inhandback) throws MBeanException, RuntimeOperationsException, IllegalArgumentException

Registers an object which implements the NotificationListener interface as a listener. This object's 'handleNotification()' method will be invoked when any attributeChangeNotification is issued through or by the ModelMBean. This does not include other Notifications. They must be registered for independently. An AttributeChangeNotification will be generated for this attributeName.

public void removeAttributeChangeNotificationListener(NotificationListener inlistener, String inAttributeName) throws MBeanException, RuntimeOperationsException, ListenerNotFoundException

Removes a listener for attributeChangeNotifications from the RequiredModelMBean.

public void sendAttributeChangeNotification(AttributeChangeNotification ntfyObj) throws MBeanException, RuntimeOperationsException

Sends an attributeChangeNotification which is passed in to the registered attributeChangeNotification listeners on the ModelMBean.

public void sendAttributeChangeNotification(Attribute inOldVal, Attribute inNewVal) throws MBeanException, RuntimeOperationsException

Sends an attributeChangeNotification which contains the old value and new value for the attribute to the registered AttributeChangeNotification listeners on the ModelMBean.

protected ClassLoaderRepository getClassLoaderRepository()

Return the Class Loader Repository used to perform class loading. Subclasses may wish to redefine this method in order to return the appropriate ClassLoaderRepository that should be used in this object.

public ObjectName preRegister(MBeanServer server, ObjectName name) throws Exception

Allows the MBean to perform any operations it needs before being registered in the MBean server. If the name of the MBean is not specified, the MBean can provide a name for its registration. If any exception is raised, the MBean will not be registered in the MBean server.

In order to ensure proper run-time semantics of RequireModelMBean, Any subclass of RequiredModelMBean overloading or overriding this method should call super.preRegister(server, name) in its own preRegister implementation.

public void postRegister(Boolean registrationDone)

Allows the MBean to perform any operations needed after having been registered in the MBean server or after the registration has failed.

In order to ensure proper run-time semantics of RequireModelMBean, Any subclass of RequiredModelMBean overloading or overriding this method should call super.postRegister(registrationDone) in its own postRegister implementation.

public void preDeregister() throws Exception

Allows the MBean to perform any operations it needs before being unregistered by the MBean server.

In order to ensure proper run-time semantics of RequireModelMBean, Any subclass of RequiredModelMBean overloading or overriding this method should call super.preDeregister() in its own preDeregister implementation.

public void postDeregister()

Allows the MBean to perform any operations needed after having been unregistered in the MBean server.

In order to ensure proper run-time semantics of RequireModelMBean, Any subclass of RequiredModelMBean overloading or overriding this method should call super.postDeregister() in its own postDeregister implementation.