Interface MBeanServerConnection

  • All Known Subinterfaces:
    MBeanServer, MBeanServerForwarder

    public interface MBeanServerConnection
    This interface represents a way to talk to an MBean server, whether local or remote. The MBeanServer interface, representing a local MBean server, extends this interface.
    Since:
    1.5
    • Method Detail

      • createMBean

        ObjectInstance createMBean​(String className,
                                   ObjectName name)
                            throws ReflectionException,
                                   InstanceAlreadyExistsException,
                                   MBeanRegistrationException,
                                   MBeanException,
                                   NotCompliantMBeanException,
                                   IOException

        Instantiates and registers an MBean in the MBean server. The MBean server will use its Default Loader Repository to load the class of the MBean. An object name is associated with the MBean. If the object name given is null, the MBean must provide its own name by implementing the MBeanRegistration interface and returning the name from the preRegister method.

        This method is equivalent to createMBean(className, name, (Object[]) null, (String[]) null).

        Parameters:
        className - The class name of the MBean to be instantiated.
        name - The object name of the MBean. May be null.
        Returns:
        An ObjectInstance, containing the ObjectName and the Java class name of the newly instantiated MBean. If the contained ObjectName is n, the contained Java class name is getMBeanInfo(n).getClassName().
        Throws:
        ReflectionException - Wraps a java.lang.ClassNotFoundException or a java.lang.Exception that occurred when trying to invoke the MBean's constructor.
        InstanceAlreadyExistsException - The MBean is already under the control of the MBean server.
        MBeanRegistrationException - The preRegister (MBeanRegistration interface) method of the MBean has thrown an exception. The MBean will not be registered.
        RuntimeMBeanException - If the MBean's constructor or its preRegister or postRegister method threw a RuntimeException. If the postRegister (MBeanRegistration interface) method of the MBean throws a RuntimeException, the createMBean method will throw a RuntimeMBeanException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeMBeanException can also be thrown by preRegister, in which case the MBean will not be registered.
        RuntimeErrorException - If the postRegister (MBeanRegistration interface) method of the MBean throws an Error, the createMBean method will throw a RuntimeErrorException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeErrorException can also be thrown by preRegister, in which case the MBean will not be registered.
        MBeanException - The constructor of the MBean has thrown an exception
        NotCompliantMBeanException - This class is not a JMX compliant MBean
        RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The className passed in parameter is null, the ObjectName passed in parameter contains a pattern or no ObjectName is specified for the MBean.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        MBeanRegistration
      • createMBean

        ObjectInstance createMBean​(String className,
                                   ObjectName name,
                                   ObjectName loaderName)
                            throws ReflectionException,
                                   InstanceAlreadyExistsException,
                                   MBeanRegistrationException,
                                   MBeanException,
                                   NotCompliantMBeanException,
                                   InstanceNotFoundException,
                                   IOException

        Instantiates and registers an MBean in the MBean server. The class loader to be used is identified by its object name. An object name is associated with the MBean. If the object name of the loader is null, the ClassLoader that loaded the MBean server will be used. If the MBean's object name given is null, the MBean must provide its own name by implementing the MBeanRegistration interface and returning the name from the preRegister method.

        This method is equivalent to createMBean(className, name, loaderName, (Object[]) null, (String[]) null).

        Parameters:
        className - The class name of the MBean to be instantiated.
        name - The object name of the MBean. May be null.
        loaderName - The object name of the class loader to be used.
        Returns:
        An ObjectInstance, containing the ObjectName and the Java class name of the newly instantiated MBean. If the contained ObjectName is n, the contained Java class name is getMBeanInfo(n).getClassName().
        Throws:
        ReflectionException - Wraps a java.lang.ClassNotFoundException or a java.lang.Exception that occurred when trying to invoke the MBean's constructor.
        InstanceAlreadyExistsException - The MBean is already under the control of the MBean server.
        MBeanRegistrationException - The preRegister (MBeanRegistration interface) method of the MBean has thrown an exception. The MBean will not be registered.
        RuntimeMBeanException - If the MBean's constructor or its preRegister or postRegister method threw a RuntimeException. If the postRegister (MBeanRegistration interface) method of the MBean throws a RuntimeException, the createMBean method will throw a RuntimeMBeanException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeMBeanException can also be thrown by preRegister, in which case the MBean will not be registered.
        RuntimeErrorException - If the postRegister (MBeanRegistration interface) method of the MBean throws an Error, the createMBean method will throw a RuntimeErrorException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeErrorException can also be thrown by preRegister, in which case the MBean will not be registered.
        MBeanException - The constructor of the MBean has thrown an exception
        NotCompliantMBeanException - This class is not a JMX compliant MBean
        InstanceNotFoundException - The specified class loader is not registered in the MBean server.
        RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The className passed in parameter is null, the ObjectName passed in parameter contains a pattern or no ObjectName is specified for the MBean.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        MBeanRegistration
      • createMBean

        ObjectInstance createMBean​(String className,
                                   ObjectName name,
                                   Object[] params,
                                   String[] signature)
                            throws ReflectionException,
                                   InstanceAlreadyExistsException,
                                   MBeanRegistrationException,
                                   MBeanException,
                                   NotCompliantMBeanException,
                                   IOException
        Instantiates and registers an MBean in the MBean server. The MBean server will use its Default Loader Repository to load the class of the MBean. An object name is associated with the MBean. If the object name given is null, the MBean must provide its own name by implementing the MBeanRegistration interface and returning the name from the preRegister method.
        Parameters:
        className - The class name of the MBean to be instantiated.
        name - The object name of the MBean. May be null.
        params - An array containing the parameters of the constructor to be invoked.
        signature - An array containing the signature of the constructor to be invoked.
        Returns:
        An ObjectInstance, containing the ObjectName and the Java class name of the newly instantiated MBean. If the contained ObjectName is n, the contained Java class name is getMBeanInfo(n).getClassName().
        Throws:
        ReflectionException - Wraps a java.lang.ClassNotFoundException or a java.lang.Exception that occurred when trying to invoke the MBean's constructor.
        InstanceAlreadyExistsException - The MBean is already under the control of the MBean server.
        MBeanRegistrationException - The preRegister (MBeanRegistration interface) method of the MBean has thrown an exception. The MBean will not be registered.
        RuntimeMBeanException - If the MBean's constructor or its preRegister or postRegister method threw a RuntimeException. If the postRegister (MBeanRegistration interface) method of the MBean throws a RuntimeException, the createMBean method will throw a RuntimeMBeanException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeMBeanException can also be thrown by preRegister, in which case the MBean will not be registered.
        RuntimeErrorException - If the postRegister (MBeanRegistration interface) method of the MBean throws an Error, the createMBean method will throw a RuntimeErrorException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeErrorException can also be thrown by preRegister, in which case the MBean will not be registered.
        MBeanException - The constructor of the MBean has thrown an exception
        NotCompliantMBeanException - This class is not a JMX compliant MBean
        RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The className passed in parameter is null, the ObjectName passed in parameter contains a pattern or no ObjectName is specified for the MBean.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        MBeanRegistration
      • createMBean

        ObjectInstance createMBean​(String className,
                                   ObjectName name,
                                   ObjectName loaderName,
                                   Object[] params,
                                   String[] signature)
                            throws ReflectionException,
                                   InstanceAlreadyExistsException,
                                   MBeanRegistrationException,
                                   MBeanException,
                                   NotCompliantMBeanException,
                                   InstanceNotFoundException,
                                   IOException

        Instantiates and registers an MBean in the MBean server. The class loader to be used is identified by its object name. An object name is associated with the MBean. If the object name of the loader is not specified, the ClassLoader that loaded the MBean server will be used. If the MBean object name given is null, the MBean must provide its own name by implementing the MBeanRegistration interface and returning the name from the preRegister method.

        Parameters:
        className - The class name of the MBean to be instantiated.
        name - The object name of the MBean. May be null.
        params - An array containing the parameters of the constructor to be invoked.
        signature - An array containing the signature of the constructor to be invoked.
        loaderName - The object name of the class loader to be used.
        Returns:
        An ObjectInstance, containing the ObjectName and the Java class name of the newly instantiated MBean. If the contained ObjectName is n, the contained Java class name is getMBeanInfo(n).getClassName().
        Throws:
        ReflectionException - Wraps a java.lang.ClassNotFoundException or a java.lang.Exception that occurred when trying to invoke the MBean's constructor.
        InstanceAlreadyExistsException - The MBean is already under the control of the MBean server.
        MBeanRegistrationException - The preRegister (MBeanRegistration interface) method of the MBean has thrown an exception. The MBean will not be registered.
        RuntimeMBeanException - The MBean's constructor or its preRegister or postRegister method threw a RuntimeException. If the postRegister (MBeanRegistration interface) method of the MBean throws a RuntimeException, the createMBean method will throw a RuntimeMBeanException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeMBeanException can also be thrown by preRegister, in which case the MBean will not be registered.
        RuntimeErrorException - If the postRegister method (MBeanRegistration interface) method of the MBean throws an Error, the createMBean method will throw a RuntimeErrorException, although the MBean creation and registration succeeded. In such a case, the MBean will be actually registered even though the createMBean method threw an exception. Note that RuntimeErrorException can also be thrown by preRegister, in which case the MBean will not be registered.
        MBeanException - The constructor of the MBean has thrown an exception
        NotCompliantMBeanException - This class is not a JMX compliant MBean
        InstanceNotFoundException - The specified class loader is not registered in the MBean server.
        RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The className passed in parameter is null, the ObjectName passed in parameter contains a pattern or no ObjectName is specified for the MBean.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        MBeanRegistration
      • unregisterMBean

        void unregisterMBean​(ObjectName name)
                      throws InstanceNotFoundException,
                             MBeanRegistrationException,
                             IOException
        Unregisters an MBean from the MBean server. The MBean is identified by its object name. Once the method has been invoked, the MBean may no longer be accessed by its object name.
        Parameters:
        name - The object name of the MBean to be unregistered.
        Throws:
        InstanceNotFoundException - The MBean specified is not registered in the MBean server.
        MBeanRegistrationException - The preDeregister ((MBeanRegistration interface) method of the MBean has thrown an exception.
        RuntimeMBeanException - If the postDeregister (MBeanRegistration interface) method of the MBean throws a RuntimeException, the unregisterMBean method will throw a RuntimeMBeanException, although the MBean unregistration succeeded. In such a case, the MBean will be actually unregistered even though the unregisterMBean method threw an exception. Note that RuntimeMBeanException can also be thrown by preDeregister, in which case the MBean will remain registered.
        RuntimeErrorException - If the postDeregister (MBeanRegistration interface) method of the MBean throws an Error, the unregisterMBean method will throw a RuntimeErrorException, although the MBean unregistration succeeded. In such a case, the MBean will be actually unregistered even though the unregisterMBean method threw an exception. Note that RuntimeMBeanException can also be thrown by preDeregister, in which case the MBean will remain registered.
        RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The object name in parameter is null or the MBean you are when trying to unregister is the MBeanServerDelegate MBean.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        MBeanRegistration
      • getObjectInstance

        ObjectInstance getObjectInstance​(ObjectName name)
                                  throws InstanceNotFoundException,
                                         IOException
        Gets the ObjectInstance for a given MBean registered with the MBean server.
        Parameters:
        name - The object name of the MBean.
        Returns:
        The ObjectInstance associated with the MBean specified by name. The contained ObjectName is name and the contained class name is getMBeanInfo(name).getClassName().
        Throws:
        InstanceNotFoundException - The MBean specified is not registered in the MBean server.
        IOException - A communication problem occurred when talking to the MBean server.
      • queryMBeans

        Set<ObjectInstance> queryMBeans​(ObjectName name,
                                        QueryExp query)
                                 throws IOException
        Gets MBeans controlled by the MBean server. This method allows any of the following to be obtained: All MBeans, a set of MBeans specified by pattern matching on the ObjectName and/or a Query expression, a specific MBean. When the object name is null or no domain and key properties are specified, all objects are to be selected (and filtered if a query is specified). It returns the set of ObjectInstance objects (containing the ObjectName and the Java Class name) for the selected MBeans.
        Parameters:
        name - The object name pattern identifying the MBeans to be retrieved. If null or no domain and key properties are specified, all the MBeans registered will be retrieved.
        query - The query expression to be applied for selecting MBeans. If null no query expression will be applied for selecting MBeans.
        Returns:
        A set containing the ObjectInstance objects for the selected MBeans. If no MBean satisfies the query an empty list is returned.
        Throws:
        IOException - A communication problem occurred when talking to the MBean server.
      • queryNames

        Set<ObjectName> queryNames​(ObjectName name,
                                   QueryExp query)
                            throws IOException
        Gets the names of MBeans controlled by the MBean server. This method enables any of the following to be obtained: The names of all MBeans, the names of a set of MBeans specified by pattern matching on the ObjectName and/or a Query expression, a specific MBean name (equivalent to testing whether an MBean is registered). When the object name is null or no domain and key properties are specified, all objects are selected (and filtered if a query is specified). It returns the set of ObjectNames for the MBeans selected.
        Parameters:
        name - The object name pattern identifying the MBean names to be retrieved. If null or no domain and key properties are specified, the name of all registered MBeans will be retrieved.
        query - The query expression to be applied for selecting MBeans. If null no query expression will be applied for selecting MBeans.
        Returns:
        A set containing the ObjectNames for the MBeans selected. If no MBean satisfies the query, an empty list is returned.
        Throws:
        IOException - A communication problem occurred when talking to the MBean server.
      • isRegistered

        boolean isRegistered​(ObjectName name)
                      throws IOException
        Checks whether an MBean, identified by its object name, is already registered with the MBean server.
        Parameters:
        name - The object name of the MBean to be checked.
        Returns:
        True if the MBean is already registered in the MBean server, false otherwise.
        Throws:
        RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The object name in parameter is null.
        IOException - A communication problem occurred when talking to the MBean server.
      • getMBeanCount

        Integer getMBeanCount()
                       throws IOException
        Returns the number of MBeans registered in the MBean server.
        Returns:
        the number of MBeans registered.
        Throws:
        IOException - A communication problem occurred when talking to the MBean server.
      • getAttributes

        AttributeList getAttributes​(ObjectName name,
                                    String[] attributes)
                             throws InstanceNotFoundException,
                                    ReflectionException,
                                    IOException

        Retrieves the values of several attributes of a named MBean. The MBean is identified by its object name.

        If one or more attributes cannot be retrieved for some reason, they will be omitted from the returned AttributeList. The caller should check that the list is the same size as the attributes array. To discover what problem prevented a given attribute from being retrieved, call getAttribute for that attribute.

        Here is an example of calling this method and checking that it succeeded in retrieving all the requested attributes:

         String[] attrNames = ...;
         AttributeList list = mbeanServerConnection.getAttributes(objectName, attrNames);
         if (list.size() == attrNames.length)
             System.out.println("All attributes were retrieved successfully");
         else {
             List<String> missing = new ArrayList<String>(Arrays.asList(attrNames));
             for (Attribute a : list.asList())
                 missing.remove(a.getName());
             System.out.println("Did not retrieve: " + missing);
         }
         
        Parameters:
        name - The object name of the MBean from which the attributes are retrieved.
        attributes - A list of the attributes to be retrieved.
        Returns:
        The list of the retrieved attributes.
        Throws:
        InstanceNotFoundException - The MBean specified is not registered in the MBean server.
        ReflectionException - An exception occurred when trying to invoke the getAttributes method of a Dynamic MBean.
        RuntimeOperationsException - Wrap a java.lang.IllegalArgumentException: The object name in parameter is null or attributes in parameter is null.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        setAttributes(javax.management.ObjectName, javax.management.AttributeList)
      • setAttributes

        AttributeList setAttributes​(ObjectName name,
                                    AttributeList attributes)
                             throws InstanceNotFoundException,
                                    ReflectionException,
                                    IOException

        Sets the values of several attributes of a named MBean. The MBean is identified by its object name.

        If one or more attributes cannot be set for some reason, they will be omitted from the returned AttributeList. The caller should check that the input AttributeList is the same size as the output one. To discover what problem prevented a given attribute from being retrieved, it will usually be possible to call setAttribute for that attribute, although this is not guaranteed to work. (For example, the values of two attributes may have been rejected because they were inconsistent with each other. Setting one of them alone might be allowed.)

        Here is an example of calling this method and checking that it succeeded in setting all the requested attributes:

         AttributeList inputAttrs = ...;
         AttributeList outputAttrs = mbeanServerConnection.setAttributes(objectName, inputAttrs);
         if (inputAttrs.size() == outputAttrs.size())
             System.out.println("All attributes were set successfully");
         else {
             List<String> missing = new ArrayList<String>();
             for (Attribute a : inputAttrs.asList())
                 missing.add(a.getName());
             for (Attribute a : outputAttrs.asList())
                 missing.remove(a.getName());
             System.out.println("Did not set: " + missing);
         }
         
        Parameters:
        name - The object name of the MBean within which the attributes are to be set.
        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.
        Throws:
        InstanceNotFoundException - The MBean specified is not registered in the MBean server.
        ReflectionException - An exception occurred when trying to invoke the getAttributes method of a Dynamic MBean.
        RuntimeOperationsException - Wraps a java.lang.IllegalArgumentException: The object name in parameter is null or attributes in parameter is null.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        getAttributes(javax.management.ObjectName, java.lang.String[])
      • invoke

        Object invoke​(ObjectName name,
                      String operationName,
                      Object[] params,
                      String[] signature)
               throws InstanceNotFoundException,
                      MBeanException,
                      ReflectionException,
                      IOException

        Invokes an operation on an MBean.

        Because of the need for a signature to differentiate possibly-overloaded operations, it is much simpler to invoke operations through an MBean proxy where possible. For example, suppose you have a Standard MBean interface like this:

         public interface FooMBean {
             public int countMatches(String[] patterns, boolean ignoreCase);
         }
         

        The countMatches operation can be invoked as follows:

         String[] myPatterns = ...;
         int count = (Integer) mbeanServerConnection.invoke(
                 objectName,
                 "countMatches",
                 new Object[] {myPatterns, true},
                 new String[] {String[].class.getName(), boolean.class.getName()});
         

        Alternatively, it can be invoked through a proxy as follows:

         String[] myPatterns = ...;
         FooMBean fooProxy = JMX.newMBeanProxy(
                 mbeanServerConnection, objectName, FooMBean.class);
         int count = fooProxy.countMatches(myPatterns, true);
         
        Parameters:
        name - The object name of the MBean on which the method is to be invoked.
        operationName - The name of the operation to be invoked.
        params - An array containing the parameters to be set when the operation is invoked
        signature - An array containing the signature of the operation, an array of class names in the format returned by Class.getName(). The class objects will be loaded using the same class loader as the one used for loading the MBean on which the operation was invoked.
        Returns:
        The object returned by the operation, which represents the result of invoking the operation on the MBean specified.
        Throws:
        InstanceNotFoundException - The MBean specified is not registered in the MBean server.
        MBeanException - Wraps an exception thrown by the MBean's invoked method.
        ReflectionException - Wraps a java.lang.Exception thrown while trying to invoke the method.
        IOException - A communication problem occurred when talking to the MBean server.
      • getDefaultDomain

        String getDefaultDomain()
                         throws IOException
        Returns the default domain used for naming the MBean. The default domain name is used as the domain part in the ObjectName of MBeans if no domain is specified by the user.
        Returns:
        the default domain.
        Throws:
        IOException - A communication problem occurred when talking to the MBean server.
      • getDomains

        String[] getDomains()
                     throws IOException

        Returns the list of domains in which any MBean is currently registered. A string is in the returned array if and only if there is at least one MBean registered with an ObjectName whose getDomain() is equal to that string. The order of strings within the returned array is not defined.

        Returns:
        the list of domains.
        Throws:
        IOException - A communication problem occurred when talking to the MBean server.
      • addNotificationListener

        void addNotificationListener​(ObjectName name,
                                     ObjectName listener,
                                     NotificationFilter filter,
                                     Object handback)
                              throws InstanceNotFoundException,
                                     IOException

        Adds a listener to a registered MBean.

        A notification emitted by an MBean will be forwarded by the MBeanServer to the listener. If the source of the notification is a reference to an MBean object, the MBean server will replace it by that MBean's ObjectName. Otherwise the source is unchanged.

        The listener object that receives notifications is the one that is registered with the given name at the time this method is called. Even if it is subsequently unregistered, it will continue to receive notifications.

        Parameters:
        name - The name of the MBean on which the listener should be added.
        listener - The object name of the listener which will handle the notifications emitted by the registered MBean.
        filter - The filter object. If filter is null, no filtering will be performed before handling notifications.
        handback - The context to be sent to the listener when a notification is emitted.
        Throws:
        InstanceNotFoundException - The MBean name of the notification listener or of the notification broadcaster does not match any of the registered MBeans.
        RuntimeOperationsException - Wraps an IllegalArgumentException. The MBean named by listener exists but does not implement the NotificationListener interface.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        removeNotificationListener(ObjectName, ObjectName), removeNotificationListener(ObjectName, ObjectName, NotificationFilter, Object)
      • removeNotificationListener

        void removeNotificationListener​(ObjectName name,
                                        ObjectName listener,
                                        NotificationFilter filter,
                                        Object handback)
                                 throws InstanceNotFoundException,
                                        ListenerNotFoundException,
                                        IOException

        Removes a listener from a registered 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.

        Parameters:
        name - The name of the MBean on which the listener should be removed.
        listener - The object name of the listener to be removed.
        filter - The filter that was specified when the listener was added.
        handback - The handback that was specified when the listener was added.
        Throws:
        InstanceNotFoundException - The MBean name provided does not match any of the registered MBeans.
        ListenerNotFoundException - The listener is not registered in the MBean, or it is not registered with the given filter and handback.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        addNotificationListener(ObjectName, ObjectName, NotificationFilter, Object)
      • isInstanceOf

        boolean isInstanceOf​(ObjectName name,
                             String className)
                      throws InstanceNotFoundException,
                             IOException

        Returns true if the MBean specified is an instance of the specified class, false otherwise.

        If name does not name an MBean, this method throws InstanceNotFoundException.

        Otherwise, let
        X be the MBean named by name,
        L be the ClassLoader of X,
        N be the class name in X's MBeanInfo.

        If N equals className, the result is true.

        Otherwise, if L successfully loads className and X is an instance of this class, the result is true.

        Otherwise, if L successfully loads both N and className, and the second class is assignable from the first, the result is true.

        Otherwise, the result is false.

        Parameters:
        name - The ObjectName of the MBean.
        className - The name of the class.
        Returns:
        true if the MBean specified is an instance of the specified class according to the rules above, false otherwise.
        Throws:
        InstanceNotFoundException - The MBean specified is not registered in the MBean server.
        IOException - A communication problem occurred when talking to the MBean server.
        See Also:
        Class.isInstance(java.lang.Object)