public class StandardMBean extends Object implements DynamicMBean, MBeanRegistration
An MBean whose management interface is determined by reflection on a Java interface.
This class brings more flexibility to the notion of Management Interface in the use of Standard MBeans. Straightforward use of the patterns for Standard MBeans described in the JMX Specification means that there is a fixed relationship between the implementation class of an MBean and its management interface (i.e., if the implementation class is Thing, the management interface must be ThingMBean). This class makes it possible to keep the convenience of specifying the management interface with a Java interface, without requiring that there be any naming relationship between the implementation and interface classes.
By making a DynamicMBean out of an MBean, this class makes it possible to select any interface implemented by the MBean as its management interface, provided that it complies with JMX patterns (i.e., attributes defined by getter/setter etc...).
This class also provides hooks that make it possible to supply
custom descriptions and names for the MBeanInfo
returned by
the DynamicMBean interface.
Using this class, an MBean can be created with any implementation class name Impl and with a management interface defined (as for current Standard MBeans) by any interface Intf, in one of two general ways:
StandardMBean(impl,interface)
:
MBeanServer mbs; ... Impl impl = new Impl(...); StandardMBean mbean = new StandardMBean(impl, Intf.class, false); mbs.registerMBean(mbean, objectName);
public class Impl extends StandardMBean implements Intf { public Impl() { super(Intf.class, false); } // implement methods of Intf } [...] MBeanServer mbs; .... Impl impl = new Impl(); mbs.registerMBean(impl, objectName);
In either case, the class Impl must implement the interface Intf.
Standard MBeans based on the naming relationship between implementation and interface classes are of course still available.
This class may also be used to construct MXBeans. The usage
is exactly the same as for Standard MBeans except that in the
examples above, the false
parameter to the constructor or
super(...)
invocation is instead true
.
Modifier | Constructor and Description |
---|---|
protected |
StandardMBean(Class<?> mbeanInterface)
Make a DynamicMBean out of this, using the specified
mbeanInterface class.
|
protected |
StandardMBean(Class<?> mbeanInterface,
boolean isMXBean)
Make a DynamicMBean out of this, using the specified
mbeanInterface class, and choosing whether the resulting
MBean is an MXBean.
|
|
StandardMBean(T implementation,
Class<T> mbeanInterface)
Make a DynamicMBean out of the object
implementation, using the specified
mbeanInterface class.
|
|
StandardMBean(T implementation,
Class<T> mbeanInterface,
boolean isMXBean)
Make a DynamicMBean out of the object
implementation, using the specified
mbeanInterface class, and choosing whether the
resultant MBean is an MXBean.
|
Modifier and Type | Method and Description |
---|---|
protected void |
cacheMBeanInfo(MBeanInfo info)
Customization hook:
cache the MBeanInfo built for this object.
|
Object |
getAttribute(String attribute)
Obtain the value of a specific attribute of the Dynamic MBean.
|
AttributeList |
getAttributes(String[] attributes)
Get the values of several attributes of the Dynamic MBean.
|
protected MBeanInfo |
getCachedMBeanInfo()
Customization hook:
Return the MBeanInfo cached for this object.
|
protected String |
getClassName(MBeanInfo info)
Customization hook:
Get the className that will be used in the MBeanInfo returned by
this MBean.
|
protected MBeanConstructorInfo[] |
getConstructors(MBeanConstructorInfo[] ctors,
Object impl)
Customization hook:
Get the MBeanConstructorInfo[] that will be used in the MBeanInfo
returned by this MBean.
|
protected String |
getDescription(MBeanAttributeInfo info)
Customization hook:
Get the description that will be used in the MBeanAttributeInfo
returned by this MBean.
|
protected String |
getDescription(MBeanConstructorInfo info)
Customization hook:
Get the description that will be used in the MBeanConstructorInfo
returned by this MBean.
|
protected String |
getDescription(MBeanConstructorInfo ctor,
MBeanParameterInfo param,
int sequence)
Customization hook:
Get the description that will be used for the sequence
MBeanParameterInfo of the MBeanConstructorInfo returned by this MBean.
|
protected String |
getDescription(MBeanFeatureInfo info)
Customization hook:
Get the description that will be used in the MBeanFeatureInfo
returned by this MBean.
|
protected String |
getDescription(MBeanInfo info)
Customization hook:
Get the description that will be used in the MBeanInfo returned by
this MBean.
|
protected String |
getDescription(MBeanOperationInfo info)
Customization hook:
Get the description that will be used in the MBeanOperationInfo
returned by this MBean.
|
protected String |
getDescription(MBeanOperationInfo op,
MBeanParameterInfo param,
int sequence)
Customization hook:
Get the description that will be used for the sequence
MBeanParameterInfo of the MBeanOperationInfo returned by this MBean.
|
protected int |
getImpact(MBeanOperationInfo info)
Customization hook:
Get the impact flag of the operation that will be used in
the MBeanOperationInfo returned by this MBean.
|
Object |
getImplementation()
Get the implementation of this Standard MBean (or MXBean).
|
Class<?> |
getImplementationClass()
Get the class of the implementation of this Standard MBean (or MXBean).
|
MBeanInfo |
getMBeanInfo()
Get the
MBeanInfo for this MBean. |
Class<?> |
getMBeanInterface()
Get the Management Interface of this Standard MBean (or MXBean).
|
protected String |
getParameterName(MBeanConstructorInfo ctor,
MBeanParameterInfo param,
int sequence)
Customization hook:
Get the name that will be used for the sequence
MBeanParameterInfo of the MBeanConstructorInfo returned by this MBean.
|
protected String |
getParameterName(MBeanOperationInfo op,
MBeanParameterInfo param,
int sequence)
Customization hook:
Get the name that will be used for the sequence
MBeanParameterInfo of the MBeanOperationInfo returned by this MBean.
|
Object |
invoke(String actionName,
Object[] params,
String[] signature)
Allows an action to be invoked on the Dynamic MBean.
|
void |
postDeregister()
Allows the MBean to perform any operations needed after having been
unregistered in the MBean server.
|
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.
|
void |
preDeregister()
Allows the MBean to perform any operations it needs before
being unregistered by the MBean server.
|
ObjectName |
preRegister(MBeanServer server,
ObjectName name)
Allows the MBean to perform any operations it needs before
being registered in the MBean server.
|
void |
setAttribute(Attribute attribute)
Set the value of a specific attribute of the Dynamic MBean.
|
AttributeList |
setAttributes(AttributeList attributes)
Sets the values of several attributes of the Dynamic MBean.
|
void |
setImplementation(Object implementation)
Replace the implementation object wrapped in this object.
|
public StandardMBean(T implementation, Class<T> mbeanInterface) throws NotCompliantMBeanException
Make a DynamicMBean out of the object implementation, using the specified mbeanInterface class.
T
- Allows the compiler to check
that implementation
does indeed implement the class
described by mbeanInterface
. The compiler can only
check this if mbeanInterface
is a class literal such
as MyMBean.class
.implementation
- The implementation of this MBean.mbeanInterface
- The Management Interface exported by this
MBean's implementation. If null
, then this
object will use standard JMX design pattern to determine
the management interface associated with the given
implementation.IllegalArgumentException
- if the given
implementation is null.NotCompliantMBeanException
- if the mbeanInterface
does not follow JMX design patterns for Management Interfaces, or
if the given implementation does not implement the
specified interface.protected StandardMBean(Class<?> mbeanInterface) throws NotCompliantMBeanException
Make a DynamicMBean out of this, using the specified mbeanInterface class.
Calls this(this,mbeanInterface)
.
This constructor is reserved to subclasses.
mbeanInterface
- The Management Interface exported by this
MBean.NotCompliantMBeanException
- if the mbeanInterface
does not follow JMX design patterns for Management Interfaces, or
if this does not implement the specified interface.public StandardMBean(T implementation, Class<T> mbeanInterface, boolean isMXBean)
Make a DynamicMBean out of the object
implementation, using the specified
mbeanInterface class, and choosing whether the
resultant MBean is an MXBean. This constructor can be used
to make either Standard MBeans or MXBeans. Unlike the
constructor StandardMBean(Object, Class)
, it
does not throw NotCompliantMBeanException.
T
- Allows the compiler to check
that implementation
does indeed implement the class
described by mbeanInterface
. The compiler can only
check this if mbeanInterface
is a class literal such
as MyMBean.class
.implementation
- The implementation of this MBean.mbeanInterface
- The Management Interface exported by this
MBean's implementation. If null
, then this
object will use standard JMX design pattern to determine
the management interface associated with the given
implementation.isMXBean
- If true, the mbeanInterface
parameter
names an MXBean interface and the resultant MBean is an MXBean.IllegalArgumentException
- if the given
implementation is null, or if the mbeanInterface
does not follow JMX design patterns for Management Interfaces, or
if the given implementation does not implement the
specified interface.protected StandardMBean(Class<?> mbeanInterface, boolean isMXBean)
Make a DynamicMBean out of this, using the specified
mbeanInterface class, and choosing whether the resulting
MBean is an MXBean. This constructor can be used
to make either Standard MBeans or MXBeans. Unlike the
constructor StandardMBean(Object, Class)
, it
does not throw NotCompliantMBeanException.
Calls this(this, mbeanInterface, isMXBean)
.
This constructor is reserved to subclasses.
mbeanInterface
- The Management Interface exported by this
MBean.isMXBean
- If true, the mbeanInterface
parameter
names an MXBean interface and the resultant MBean is an MXBean.IllegalArgumentException
- if the mbeanInterface
does not follow JMX design patterns for Management Interfaces, or
if this does not implement the specified interface.public void setImplementation(Object implementation) throws NotCompliantMBeanException
Replace the implementation object wrapped in this object.
implementation
- The new implementation of this Standard MBean
(or MXBean). The implementation
object must implement
the Standard MBean (or MXBean) interface that was supplied when this
StandardMBean
was constructed.IllegalArgumentException
- if the given
implementation is null.NotCompliantMBeanException
- if the given
implementation does not implement the
Standard MBean (or MXBean) interface that was
supplied at construction.getImplementation()
public Object getImplementation()
setImplementation(java.lang.Object)
public final Class<?> getMBeanInterface()
public Class<?> getImplementationClass()
public Object getAttribute(String attribute) throws AttributeNotFoundException, MBeanException, ReflectionException
DynamicMBean
getAttribute
in interface DynamicMBean
attribute
- The name of the attribute to be retrievedAttributeNotFoundException
MBeanException
- Wraps a java.lang.Exception
thrown by the MBean's getter.ReflectionException
- Wraps a java.lang.Exception
thrown while trying to invoke the getter.DynamicMBean.setAttribute(javax.management.Attribute)
public void setAttribute(Attribute attribute) throws AttributeNotFoundException, InvalidAttributeValueException, MBeanException, ReflectionException
DynamicMBean
setAttribute
in interface DynamicMBean
attribute
- The identification of the attribute to
be set and the value it is to be set to.AttributeNotFoundException
InvalidAttributeValueException
MBeanException
- Wraps a java.lang.Exception
thrown by the MBean's setter.ReflectionException
- Wraps a java.lang.Exception
thrown while trying to invoke the MBean's setter.DynamicMBean.getAttribute(java.lang.String)
public AttributeList getAttributes(String[] attributes)
DynamicMBean
getAttributes
in interface DynamicMBean
attributes
- A list of the attributes to be retrieved.DynamicMBean.setAttributes(javax.management.AttributeList)
public AttributeList setAttributes(AttributeList attributes)
DynamicMBean
setAttributes
in interface DynamicMBean
attributes
- A list of attributes: The identification of the
attributes to be set and the values they are to be set to.DynamicMBean.getAttributes(java.lang.String[])
public Object invoke(String actionName, Object[] params, String[] signature) throws MBeanException, ReflectionException
DynamicMBean
invoke
in interface DynamicMBean
actionName
- The name of the action to be invoked.params
- An array containing the parameters to be set when the action is
invoked.signature
- An array containing the signature of the action. The class objects will
be loaded through the same class loader as the one used for loading the
MBean on which the action is invoked.MBeanException
- Wraps a java.lang.Exception
thrown by the MBean's invoked method.ReflectionException
- Wraps a java.lang.Exception
thrown while trying to invoke the methodpublic MBeanInfo getMBeanInfo()
MBeanInfo
for this MBean.
This method implements
DynamicMBean.getMBeanInfo()
.
This method first calls getCachedMBeanInfo()
in order to
retrieve the cached MBeanInfo for this MBean, if any. If the
MBeanInfo returned by getCachedMBeanInfo()
is not null,
then it is returned.
Otherwise, this method builds a default MBeanInfo for this MBean,
using the Management Interface specified for this MBean.
While building the MBeanInfo, this method calls the customization
hooks that make it possible for subclasses to supply their custom
descriptions, parameter names, etc...
Finally, it calls cacheMBeanInfo()
in order to cache the new MBeanInfo.
getMBeanInfo
in interface DynamicMBean
protected String getClassName(MBeanInfo info)
info.getClassName()
.info
- The default MBeanInfo derived by reflection.protected String getDescription(MBeanInfo info)
info.getDescription()
.info
- The default MBeanInfo derived by reflection.protected String getDescription(MBeanFeatureInfo info)
Customization hook: Get the description that will be used in the MBeanFeatureInfo returned by this MBean.
Subclasses may redefine this method in order to supply
their custom description. The default implementation returns
info.getDescription()
.
This method is called by
getDescription(MBeanAttributeInfo)
,
getDescription(MBeanOperationInfo)
,
getDescription(MBeanConstructorInfo)
.
info
- The default MBeanFeatureInfo derived by reflection.protected String getDescription(MBeanAttributeInfo info)
Subclasses may redefine this method in order to supply their
custom description. The default implementation returns getDescription((MBeanFeatureInfo) info)
.
info
- The default MBeanAttributeInfo derived by reflection.protected String getDescription(MBeanConstructorInfo info)
getDescription((MBeanFeatureInfo) info)
.info
- The default MBeanConstructorInfo derived by reflection.protected String getDescription(MBeanConstructorInfo ctor, MBeanParameterInfo param, int sequence)
param.getDescription()
.ctor
- The default MBeanConstructorInfo derived by reflection.param
- The default MBeanParameterInfo derived by reflection.sequence
- The sequence number of the parameter considered
("0" for the first parameter, "1" for the second parameter,
etc...).protected String getParameterName(MBeanConstructorInfo ctor, MBeanParameterInfo param, int sequence)
param.getName()
.ctor
- The default MBeanConstructorInfo derived by reflection.param
- The default MBeanParameterInfo derived by reflection.sequence
- The sequence number of the parameter considered
("0" for the first parameter, "1" for the second parameter,
etc...).protected String getDescription(MBeanOperationInfo info)
getDescription((MBeanFeatureInfo) info)
.info
- The default MBeanOperationInfo derived by reflection.protected int getImpact(MBeanOperationInfo info)
info.getImpact()
.info
- The default MBeanOperationInfo derived by reflection.protected String getParameterName(MBeanOperationInfo op, MBeanParameterInfo param, int sequence)
param.getName()
.op
- The default MBeanOperationInfo derived by reflection.param
- The default MBeanParameterInfo derived by reflection.sequence
- The sequence number of the parameter considered
("0" for the first parameter, "1" for the second parameter,
etc...).protected String getDescription(MBeanOperationInfo op, MBeanParameterInfo param, int sequence)
param.getDescription()
.op
- The default MBeanOperationInfo derived by reflection.param
- The default MBeanParameterInfo derived by reflection.sequence
- The sequence number of the parameter considered
("0" for the first parameter, "1" for the second parameter,
etc...).protected MBeanConstructorInfo[] getConstructors(MBeanConstructorInfo[] ctors, Object impl)
null
if the wrapped
implementation is not this. Indeed, if the wrapped
implementation is not this object itself, it will not be possible
to recreate a wrapped implementation by calling the implementation
constructors through MBeanServer.createMBean(...)
.ctors
- The default MBeanConstructorInfo[] derived by reflection.impl
- The wrapped implementation. If null
is
passed, the wrapped implementation is ignored and
ctors is returned.protected MBeanInfo getCachedMBeanInfo()
Subclasses may redefine this method in order to implement their
own caching policy. The default implementation stores one
MBeanInfo
object per instance.
cacheMBeanInfo(MBeanInfo)
protected void cacheMBeanInfo(MBeanInfo info)
Subclasses may redefine this method in order to implement
their own caching policy. The default implementation stores
info
in this instance. A subclass can define
other policies, such as not saving info
(so it is
reconstructed every time getMBeanInfo()
is called) or
sharing a unique MBeanInfo
object when several
StandardMBean
instances have equal MBeanInfo
values.
info
- the new MBeanInfo
to cache. Any
previously cached value is discarded. This parameter may be
null, in which case there is no new cached value.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.
The default implementation of this method returns the name
parameter. It does nothing else for
Standard MBeans. For MXBeans, it records the MBeanServer
and ObjectName
parameters so they can be used to translate
inter-MXBean references.
It is good practice for a subclass that overrides this method
to call the overridden method via super.preRegister(...)
.
This is necessary if this object is an MXBean that is referenced
by attributes or operations in other MXBeans.
preRegister
in interface MBeanRegistration
server
- The MBean server in which the MBean will be registered.name
- The object name of the MBean. This name is null if
the name parameter to one of the createMBean
or
registerMBean
methods in the MBeanServer
interface is null. In that case, this method must return a
non-null ObjectName for the new MBean.name
parameter is not null, it will usually but not necessarily be
the returned value.IllegalArgumentException
- if this is an MXBean and
name
is null.InstanceAlreadyExistsException
- if this is an MXBean and
it has already been registered under another name (in this
MBean Server or another).Exception
- no other checked exceptions are thrown by
this method but Exception
is declared so that subclasses
can override the method and throw their own exceptions.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.
The default implementation of this method does nothing for
Standard MBeans. For MXBeans, it undoes any work done by
preRegister
if registration fails.
It is good practice for a subclass that overrides this method
to call the overridden method via super.postRegister(...)
.
This is necessary if this object is an MXBean that is referenced
by attributes or operations in other MXBeans.
postRegister
in interface MBeanRegistration
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.public void preDeregister() throws Exception
Allows the MBean to perform any operations it needs before being unregistered by the MBean server.
The default implementation of this method does nothing.
It is good practice for a subclass that overrides this method
to call the overridden method via super.preDeregister(...)
.
preDeregister
in interface MBeanRegistration
Exception
- no checked exceptions are throw by this method
but Exception
is declared so that subclasses can override
this method and throw their own exceptions.public void postDeregister()
Allows the MBean to perform any operations needed after having been unregistered in the MBean server.
The default implementation of this method does nothing for
Standard MBeans. For MXBeans, it removes any information that
was recorded by the preRegister
method.
It is good practice for a subclass that overrides this method
to call the overridden method via super.postRegister(...)
.
This is necessary if this object is an MXBean that is referenced
by attributes or operations in other MXBeans.
postDeregister
in interface MBeanRegistration
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