org.apache.derby.impl.services.jmx

Class JMXManagementService

java.lang.Object

org.apache.derby.impl.services.jmx.JMXManagementService

All Implemented Interfaces:

ManagementService, ModuleControl, ManagementMBean

public final class JMXManagementService
extends java.lang.Object
implements ManagementService, ModuleControl

This class implements the ManagementService interface and provides a simple management and monitoring service. An mbean registered with this service remains until it is unregistered. While registered with this service it may be registered and unregistered with the jmx service a number of times.

See Also:

ManagementService

Field Summary

Fields

Modifier and Type	Field and Description
private static SystemPermission	CONTROL Control permission (permissions are immutable).
private javax.management.MBeanServer	mbeanServer Platform MBean server, from ManagementFactory.getPlatformMBeanServer().
private javax.management.ObjectName	myManagementBean If this object is registered as a management mbean then myManagementBean represents its name.
private javax.management.MBeanServer	myManagementServer
private java.util.Map<javax.management.ObjectName,javax.management.StandardMBean>	registeredMbeans The set of mbeans registered to this service by Derby's code.
private java.lang.String	systemIdentifier Runtime value to disambiguate multiple Derby systems in the same virtual machine but different class loaders.

Fields inherited from interface org.apache.derby.iapi.services.jmx.ManagementService

DERBY_JMX_DOMAIN

Constructor Summary

Constructors

Constructor and Description
JMXManagementService()

Method Summary

Methods

Modifier and Type	Method and Description
void	boot(boolean create, java.util.Properties properties) Start the management service if derby.system.jmx is true.
private void	checkJMXControl() Require SystemPermission("jmx", "control") to change the management state.
private void	findServer() Initialize the management service by obtaining the platform MBeanServer and registering system beans.
java.lang.String	getSystemIdentifier() Get the system identifier that this MBean is managing.
boolean	isManagementActive() Is Derby's JMX management active.
private void	jmxRegister(javax.management.StandardMBean standardMBean, javax.management.ObjectName beanName) Register an mbean with the platform mbean server.
private void	jmxUnregister(javax.management.ObjectName mbeanName) Unregister an mbean from the JMX plaform server but leave it registered to this service.
java.lang.Object	registerMBean(java.lang.Object bean, java.lang.Class beanInterface, java.lang.String keyProperties) Registers an MBean with the MBean server as a StandardMBean.
void	startManagement() Inform Derby to start its JMX management by registering MBeans relevant to its current state.
void	stop() Stop the module.
void	stopManagement() Inform Derby to stop its JMX management by unregistering its MBeans.
void	unregisterMBean(java.lang.Object mbeanIdentifier) Unregister an mbean using an object previous returned from registerMBean.
private void	unregisterMBean(javax.management.ObjectName mbeanName) Unregisters an mbean from this service and JMX plaform server

Methods inherited from class java.lang.Object

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

Field Detail

mbeanServer

private javax.management.MBeanServer mbeanServer

Platform MBean server, from ManagementFactory.getPlatformMBeanServer(). If not null then this service has registered mbeans with the plaform MBean server. If null then this service either has no mbeans registered or one mbean registered (representing itself).

registeredMbeans

private java.util.Map<javax.management.ObjectName,javax.management.StandardMBean> registeredMbeans

The set of mbeans registered to this service by Derby's code. These beans are registered with the platform mbean server if mbeanServer is not null.

myManagementBean

private javax.management.ObjectName myManagementBean

If this object is registered as a management mbean then myManagementBean represents its name. This will be non-null when derby.system.jmx is true.

myManagementServer

private javax.management.MBeanServer myManagementServer

systemIdentifier

private java.lang.String systemIdentifier

Runtime value to disambiguate multiple Derby systems in the same virtual machine but different class loaders. Set as the system attribute in the ObjectName for all MBeans registered.

CONTROL

private static final SystemPermission CONTROL

Control permission (permissions are immutable).

Constructor Detail

JMXManagementService

public JMXManagementService()

Method Detail

boot

public void boot(boolean create,
        java.util.Properties properties)
          throws StandardException

Start the management service if derby.system.jmx is true.

Starting the service means:

• getting the platform MBeanServer which may require starting it
• registering a Version mbean representing the system

Specified by:

boot in interface ModuleControl

Throws:

StandardException - Module cannot be started.

See Also:

Monitor, ModuleFactory

stop

public void stop()

Description copied from interface: ModuleControl

Stop the module. The module may be found via a findModule() method until some time after this method returns. Therefore the factory must be prepared to reject requests to it once it has been stopped. In addition other modules may cache a reference to the module and make requests of it after it has been stopped, these requests should be rejected as well.

Specified by:

stop in interface ModuleControl

See Also:

Monitor, ModuleFactory

findServer

private void findServer()

Initialize the management service by obtaining the platform MBeanServer and registering system beans. Separate from boot() to allow future changes where the jmx management can be enabled on the fly.

registerMBean

public java.lang.Object registerMBean(java.lang.Object bean,
                             java.lang.Class beanInterface,
                             java.lang.String keyProperties)
                               throws StandardException

Registers an MBean with the MBean server as a StandardMBean. Use of the StandardMBean allows the implementation details of Derby's mbeans to be hidden from JMX, thus only exposing the MBean's interface in org.apache.derby.mbeans.

Specified by:

registerMBean in interface ManagementService

Parameters:

bean - The MBean to wrap with a StandardMBean and register

beanInterface - The management interface for the MBean.

keyProperties - The String representation of the MBean's key properties, they will be added into the ObjectName with Derby's domain. Key type should be first with a short name for the bean, typically the class name without the package.

Returns:

An idenitifier that can later be used to unregister the mbean.

Throws:

StandardException

jmxRegister

private void jmxRegister(javax.management.StandardMBean standardMBean,
               javax.management.ObjectName beanName)
                  throws javax.management.JMException

Register an mbean with the platform mbean server.

Throws:

javax.management.JMException

unregisterMBean

public void unregisterMBean(java.lang.Object mbeanIdentifier)

Unregister an mbean using an object previous returned from registerMBean.

Specified by:

unregisterMBean in interface ManagementService

Parameters:

mbeanIdentifier - An identifier returned by registerMBean.

unregisterMBean

private void unregisterMBean(javax.management.ObjectName mbeanName)

Unregisters an mbean from this service and JMX plaform server

Parameters:

mbeanName - Bean to unregister.

jmxUnregister

private void jmxUnregister(javax.management.ObjectName mbeanName)

Unregister an mbean from the JMX plaform server but leave it registered to this service. This is so that if jmx is reenabled we can reestablish all vaid mbeans (that are still registered with this service).

Parameters:

mbeanName -

isManagementActive

public boolean isManagementActive()

Description copied from interface: ManagementMBean

Is Derby's JMX management active. If active then Derby has registered MBeans relevant to its current state.

Specified by:

isManagementActive in interface ManagementMBean

Returns:

true Derby has registered beans, false Derby has not registered any beans.

startManagement

public void startManagement()

Description copied from interface: ManagementMBean

Inform Derby to start its JMX management by registering MBeans relevant to its current state. If Derby is not booted then no action is taken.

Require SystemPermission("jmx", "control") if a security manager is installed.

Specified by:

startManagement in interface ManagementMBean

See Also:

SystemPermission

stopManagement

public void stopManagement()

Description copied from interface: ManagementMBean

Inform Derby to stop its JMX management by unregistering its MBeans. If Derby is not booted then no action is taken.

Require SystemPermission("jmx", "control") if a security manager is installed.

Specified by:

stopManagement in interface ManagementMBean

See Also:

SystemPermission

checkJMXControl

private void checkJMXControl()

Require SystemPermission("jmx", "control") to change the management state.

getSystemIdentifier

public java.lang.String getSystemIdentifier()

Description copied from interface: ManagementMBean

Get the system identifier that this MBean is managing. The system identifier is a runtime value to disambiguate multiple Derby systems in the same virtual machine but different class loaders.

Specified by:

getSystemIdentifier in interface ManagementMBean

Returns:

Runtime identifier for the system, null if Derby is not running.