org.apache.geronimo.kernel.basic
Class BasicKernel

java.lang.Object
  org.apache.geronimo.kernel.basic.BasicKernel

All Implemented Interfaces:

Kernel

public class BasicKernel

extends java.lang.Object

implements Kernel

The core of a Geronimo instance. A Kernel is responsible for managing the Configurations that comprise a Geronimo system and exposing them using JMX. Each Kernel is associated with an MBeanServer that is used to register the Configurations themselves and the MBeans they define.

Dependencies between MBeans are handled by a dedicated DependencyManager that is responsible for tracking those dependencies and ensuring that the dependent objects follow the appropriate lifecycle and receive appropriate notifications.

The Kernel also provides a ConfigurationStore which is used to stage installed Configurations (providing a local filesystem based classpath) and used hold the persistent state of each Configuration. This allows Configurations to restart in the event of system failure. TODO: Describe the order of method invocation (e.g. if loadGbean may be before boot)

Version:

$Rev: 154947 $ $Date: 2005-02-22 20:10:45 -0800 (Tue, 22 Feb 2005) $

Field Summary

private java.util.Date	bootTime The timestamp when the kernel was started
private DependencyManager	dependencyManager This manager is used by the kernel to manage dependencies between gbeans
private java.lang.String	kernelName Name of this kernel
private BasicLifecycleMonitor	lifecycleMonitor Monitors the lifecycle of all gbeans.
private Log	log The log
private static java.lang.Object[]	NO_ARGS
private static java.lang.String[]	NO_TYPES Helper objects for invoke and getAttribute
private ProxyManager	proxyManager This factory gbean proxies, and tracks all proxies in the system
private LifecycleMonitor	publicLifecycleMonitor
private BasicRegistry	registry The registry
private boolean	running Is this kernel running?
private java.util.LinkedList	shutdownHooks Listeners for when the kernel shutdown

Fields inherited from interface org.apache.geronimo.kernel.Kernel

KERNEL

Constructor Summary

BasicKernel(java.lang.String kernelName)
Construct a Kernel with the specified name.

Method Summary

void	boot() Boot this Kernel, triggering the instantiation of the MBeanServer and DependencyManager, and the registration of ConfigurationStore
private GBeanName	createGBeanName(javax.management.ObjectName objectName)
java.lang.Object	getAttribute(javax.management.ObjectName objectName, java.lang.String attributeName) Gets the value of an attribute on the specified gbean
java.util.Date	getBootTime() Returns the time this kernel was last booted.
java.lang.ClassLoader	getClassLoaderFor(javax.management.ObjectName name) Gets the ClassLoader used to register the specified GBean
DependencyManager	getDependencyManager() Gets the dependency manager kernel service
GBeanData	getGBeanData(javax.management.ObjectName name) Return the GBeanData for a GBean instance.
GBeanInfo	getGBeanInfo(javax.management.ObjectName name) Return the GBeanInfo for a registered GBean instance.
long	getGBeanStartTime(javax.management.ObjectName name) Gets the time the specified GBean was started
int	getGBeanState(javax.management.ObjectName name) Gets the state of the specified GBean.
java.lang.String	getKernelName() Get the name of this kernel
LifecycleMonitor	getLifecycleMonitor() Deprecated. don't use this yet... it may change or go away
ProxyManager	getProxyManager() Deprecated. don't use this yet... it may change or go away
java.lang.Object	invoke(javax.management.ObjectName objectName, java.lang.String methodName) Invokes a no-argument method on the specified GBean
java.lang.Object	invoke(javax.management.ObjectName objectName, java.lang.String methodName, java.lang.Object[] args, java.lang.String[] types) Invokes a method on the specified GBean with the specified arguments
boolean	isGBeanEnabled(javax.management.ObjectName name) Is the specified GBean enabled?
boolean	isLoaded(javax.management.ObjectName name) Is there a GBean registered with the kernel under the specified name?
boolean	isRunning() Has the kernel been booted
java.util.Set	listGBeans(javax.management.ObjectName pattern) Returns a Set of all GBeans matching the object name pattern
java.util.Set	listGBeans(java.util.Set patterns) Returns a Set of all GBeans matching the set of object name pattern
void	loadGBean(GBeanData gbeanData, java.lang.ClassLoader classLoader) Load a specific GBean into this kernel.
private void	notifyShutdownHooks()
void	registerShutdownHook(java.lang.Runnable hook) Registers a runnable to execute when the kernel is shutdown
void	setAttribute(javax.management.ObjectName objectName, java.lang.String attributeName, java.lang.Object attributeValue) Sets the value of an attribute on the specified gbean
void	setGBeanEnabled(javax.management.ObjectName name, boolean enabled) Sets the eneabled status of the specified GBean.
void	shutdown() Shut down this kernel instance, unregistering the MBeans and releasing the MBeanServer.
void	startGBean(javax.management.ObjectName name) Start a specific GBean.
void	startRecursiveGBean(javax.management.ObjectName name) Start a specific GBean and its children.
void	stopGBean(javax.management.ObjectName name) Stop a specific GBean.
void	unloadGBean(javax.management.ObjectName name) Unload a specific GBean.
void	unregisterShutdownHook(java.lang.Runnable hook) Unregisters a runnable from the list to execute when the kernel is shutdown

Methods inherited from class java.lang.Object

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

Field Detail

NO_TYPES

private static final java.lang.String[] NO_TYPES

Helper objects for invoke and getAttribute

NO_ARGS

private static final java.lang.Object[] NO_ARGS

kernelName

private final java.lang.String kernelName

Name of this kernel

log

private Log log

The log

running

private boolean running

Is this kernel running?

bootTime

private java.util.Date bootTime

The timestamp when the kernel was started

registry

private final BasicRegistry registry

The registry

shutdownHooks

private java.util.LinkedList shutdownHooks

Listeners for when the kernel shutdown

dependencyManager

private DependencyManager dependencyManager

This manager is used by the kernel to manage dependencies between gbeans

lifecycleMonitor

private BasicLifecycleMonitor lifecycleMonitor

Monitors the lifecycle of all gbeans.

publicLifecycleMonitor

private LifecycleMonitor publicLifecycleMonitor

proxyManager

private ProxyManager proxyManager

This factory gbean proxies, and tracks all proxies in the system

Constructor Detail

BasicKernel

public BasicKernel(java.lang.String kernelName)

Construct a Kernel with the specified name.

Parameters:

kernelName - the name of the kernel

Method Detail

getKernelName

public java.lang.String getKernelName()

Description copied from interface: Kernel

Get the name of this kernel

Specified by:

getKernelName in interface Kernel

Returns:

the name of this kernel

getDependencyManager

public DependencyManager getDependencyManager()

Deprecated. this will be removed as when we add generalized dependencies to gbeans... the only current user is Configuration

Description copied from interface: Kernel

Gets the dependency manager kernel service

Specified by:

getDependencyManager in interface Kernel

Returns:

the dependency manager or null if the kernel is not running

getLifecycleMonitor

public LifecycleMonitor getLifecycleMonitor()

Deprecated. don't use this yet... it may change or go away

Gets the lifecycle monitor.

Specified by:

getLifecycleMonitor in interface Kernel

Returns:

the lifecycle monitor or null if the kernel is not running

getProxyManager

public ProxyManager getProxyManager()

Deprecated. don't use this yet... it may change or go away

Gets the proxy manager.

Specified by:

getProxyManager in interface Kernel

Returns:

the proxy manager or null if the kernel is not running

getAttribute

public java.lang.Object getAttribute(javax.management.ObjectName objectName,
                                     java.lang.String attributeName)
                              throws GBeanNotFoundException,
                                     NoSuchAttributeException,
                                     java.lang.Exception

Description copied from interface: Kernel

Gets the value of an attribute on the specified gbean

Specified by:

getAttribute in interface Kernel

Parameters:

objectName - the name of the gbean from which the attribute will be retrieved

attributeName - the name of the attribute to fetch

Returns:

the value of the attribute

Throws:

NoSuchAttributeException - if the gbean does not contain the specified attribute

java.lang.Exception - if the gbean throws an exception from the getter

GBeanNotFoundException - if there is not a gbean under the specified name

setAttribute

public void setAttribute(javax.management.ObjectName objectName,
                         java.lang.String attributeName,
                         java.lang.Object attributeValue)
                  throws GBeanNotFoundException,
                         NoSuchAttributeException,
                         java.lang.Exception

Description copied from interface: Kernel

Sets the value of an attribute on the specified gbean

Specified by:

setAttribute in interface Kernel

Parameters:

objectName - the name of the gbean from in which the new attribute value will be set

attributeName - the name of the attribute to set

attributeValue - the new value of the attribute

Throws:

java.lang.Exception - if the gbean throws an exception from the setter

NoSuchAttributeException - if the gbean does not contain the specified attribute

GBeanNotFoundException - if there is not a gbean under the specified name

invoke

public java.lang.Object invoke(javax.management.ObjectName objectName,
                               java.lang.String methodName)
                        throws GBeanNotFoundException,
                               NoSuchOperationException,
                               InternalKernelException,
                               java.lang.Exception

Description copied from interface: Kernel

Invokes a no-argument method on the specified GBean

Specified by:

invoke in interface Kernel

Parameters:

objectName - the name of the gbean from in which the new attribute value will be set

methodName - the name of the method to invoke

Returns:

the return value of the method or null if the specified method does not return a value

Throws:

java.lang.Exception - if the method throws an exception

InternalKernelException - if an error occurs within the kernel itself

NoSuchOperationException - if the gbean does not have the specified operation

GBeanNotFoundException - if there is not a gbean under the specified name

invoke

public java.lang.Object invoke(javax.management.ObjectName objectName,
                               java.lang.String methodName,
                               java.lang.Object[] args,
                               java.lang.String[] types)
                        throws GBeanNotFoundException,
                               NoSuchOperationException,
                               InternalKernelException,
                               java.lang.Exception

Description copied from interface: Kernel

Invokes a method on the specified GBean with the specified arguments

Specified by:

invoke in interface Kernel

Parameters:

objectName - the name of the gbean from in which the new attribute value will be set

methodName - the name of the method to invoke

args - the arguments to pass to the method

types - the types of the arguments; the types are used to determine the signature of the mehod that should be invoked

Returns:

the return value of the method or null if the specified method does not return a value

Throws:

GBeanNotFoundException - if there is not a gbean under the specified name

NoSuchOperationException - if the gbean does not have the specified operation

InternalKernelException - if an error occurs within the kernel itself

java.lang.Exception - if the method throws an exception

isLoaded

public boolean isLoaded(javax.management.ObjectName name)

Description copied from interface: Kernel

Is there a GBean registered with the kernel under the specified name?

Specified by:

isLoaded in interface Kernel

Parameters:

name - the name to check

Returns:

true if there is a gbean registered under the specified name; false otherwise

getGBeanInfo

public GBeanInfo getGBeanInfo(javax.management.ObjectName name)
                       throws GBeanNotFoundException

Description copied from interface: Kernel

Return the GBeanInfo for a registered GBean instance.

Specified by:

getGBeanInfo in interface Kernel

Parameters:

name - the name of the GBean whose info should be returned

Returns:

the info for that instance

Throws:

GBeanNotFoundException - if there is no instance with the supplied name

getGBeanData

public GBeanData getGBeanData(javax.management.ObjectName name)
                       throws GBeanNotFoundException,
                              InternalKernelException

Description copied from interface: Kernel

Return the GBeanData for a GBean instance.

Specified by:

getGBeanData in interface Kernel

Parameters:

name - the name of the GBean whose info should be returned

Returns:

the info for that instance

Throws:

GBeanNotFoundException - if there is no instance with the supplied name

InternalKernelException

loadGBean

public void loadGBean(GBeanData gbeanData,
                      java.lang.ClassLoader classLoader)
               throws GBeanAlreadyExistsException,
                      InternalKernelException

Description copied from interface: Kernel

Load a specific GBean into this kernel. This is intended for applications that are embedding the kernel.

Specified by:

loadGBean in interface Kernel

Parameters:

gbeanData - the GBean to load

classLoader - the class loader to use to load the gbean

Throws:

GBeanAlreadyExistsException - if the name is already used

InternalKernelException - if there is a problem during registration

startGBean

public void startGBean(javax.management.ObjectName name)
                throws GBeanNotFoundException,
                       InternalKernelException,
                       java.lang.IllegalStateException

Description copied from interface: Kernel

Start a specific GBean.

Specified by:

startGBean in interface Kernel

Parameters:

name - the GBean to start

Throws:

java.lang.IllegalStateException - If the gbean is disabled

GBeanNotFoundException - if the GBean could not be found

InternalKernelException - if there GBean is not state manageable or if there is a general error

startRecursiveGBean

public void startRecursiveGBean(javax.management.ObjectName name)
                         throws GBeanNotFoundException,
                                InternalKernelException,
                                java.lang.IllegalStateException

Description copied from interface: Kernel

Start a specific GBean and its children.

Specified by:

startRecursiveGBean in interface Kernel

Parameters:

name - the GBean to start

Throws:

java.lang.IllegalStateException - If the gbean is disabled

GBeanNotFoundException - if the GBean could not be found

InternalKernelException - if there GBean is not state manageable or if there is a general error

stopGBean

public void stopGBean(javax.management.ObjectName name)
               throws GBeanNotFoundException,
                      InternalKernelException,
                      java.lang.IllegalStateException

Description copied from interface: Kernel

Stop a specific GBean.

Specified by:

stopGBean in interface Kernel

Parameters:

name - the GBean to stop

Throws:

GBeanNotFoundException - if the GBean could not be found

InternalKernelException - if there GBean is not state manageable or if there is a general error

java.lang.IllegalStateException - If the gbean is disabled

unloadGBean

public void unloadGBean(javax.management.ObjectName name)
                 throws GBeanNotFoundException,
                        InternalKernelException,
                        java.lang.IllegalStateException

Description copied from interface: Kernel

Unload a specific GBean. This is intended for applications that are embedding the kernel.

Specified by:

unloadGBean in interface Kernel

Parameters:

name - the name of the GBean to unregister

Throws:

InternalKernelException - if there GBean is a problem while unloading the GBean

GBeanNotFoundException - if the GBean could not be found

java.lang.IllegalStateException

getGBeanState

public int getGBeanState(javax.management.ObjectName name)
                  throws GBeanNotFoundException

Description copied from interface: Kernel

Gets the state of the specified GBean.

Specified by:

getGBeanState in interface Kernel

Parameters:

name - the name of the GBean

Returns:

the state of the GBean

Throws:

GBeanNotFoundException - if the GBean could not be found

getGBeanStartTime

public long getGBeanStartTime(javax.management.ObjectName name)
                       throws GBeanNotFoundException

Description copied from interface: Kernel

Gets the time the specified GBean was started

Specified by:

getGBeanStartTime in interface Kernel

Parameters:

name - the name of the GBean

Returns:

the start time of the GBean or 0 if not running

Throws:

GBeanNotFoundException - if the GBean could not be found

isGBeanEnabled

public boolean isGBeanEnabled(javax.management.ObjectName name)
                       throws GBeanNotFoundException

Description copied from interface: Kernel

Is the specified GBean enabled?

Specified by:

isGBeanEnabled in interface Kernel

Parameters:

name - the name if the GBean

Returns:

true if the gbean is enabled

Throws:

GBeanNotFoundException - if the GBean could not be found

setGBeanEnabled

public void setGBeanEnabled(javax.management.ObjectName name,
                            boolean enabled)
                     throws GBeanNotFoundException

Description copied from interface: Kernel

Sets the eneabled status of the specified GBean. A disabled gbean can not be started, and will not be started via startRecursive.

Specified by:

setGBeanEnabled in interface Kernel

Parameters:

name - the name if the GBean

enabled - the new enabled status

Throws:

GBeanNotFoundException - if the GBean could not be found

listGBeans

public java.util.Set listGBeans(javax.management.ObjectName pattern)

Description copied from interface: Kernel

Returns a Set of all GBeans matching the object name pattern

Specified by:

listGBeans in interface Kernel

Returns:

a List of javax.management.ObjectName of matching GBeans registered with this kernel

listGBeans

public java.util.Set listGBeans(java.util.Set patterns)

Description copied from interface: Kernel

Returns a Set of all GBeans matching the set of object name pattern

Specified by:

listGBeans in interface Kernel

Returns:

a List of javax.management.ObjectName of matching GBeans registered with this kernel

boot

public void boot()
          throws java.lang.Exception

Boot this Kernel, triggering the instantiation of the MBeanServer and DependencyManager, and the registration of ConfigurationStore

Specified by:

boot in interface Kernel

Throws:

java.lang.Exception - if the boot fails

getBootTime

public java.util.Date getBootTime()

Description copied from interface: Kernel

Returns the time this kernel was last booted.

Specified by:

getBootTime in interface Kernel

Returns:

the time this kernel was last booted; null if the kernel has not been

registerShutdownHook

public void registerShutdownHook(java.lang.Runnable hook)

Description copied from interface: Kernel

Registers a runnable to execute when the kernel is shutdown

Specified by:

registerShutdownHook in interface Kernel

Parameters:

hook - a runnable to execute when the kernel is shutdown

unregisterShutdownHook

public void unregisterShutdownHook(java.lang.Runnable hook)

Description copied from interface: Kernel

Unregisters a runnable from the list to execute when the kernel is shutdown

Specified by:

unregisterShutdownHook in interface Kernel

Parameters:

hook - the runnable that should be removed

shutdown

public void shutdown()

Shut down this kernel instance, unregistering the MBeans and releasing the MBeanServer.

Specified by:

shutdown in interface Kernel

notifyShutdownHooks

private void notifyShutdownHooks()

isRunning

public boolean isRunning()

Description copied from interface: Kernel

Has the kernel been booted

Specified by:

isRunning in interface Kernel

Returns:

true if the kernel has been booted; false otherwise

getClassLoaderFor

public java.lang.ClassLoader getClassLoaderFor(javax.management.ObjectName name)
                                        throws GBeanNotFoundException

Description copied from interface: Kernel

Gets the ClassLoader used to register the specified GBean

Specified by:

getClassLoaderFor in interface Kernel

Parameters:

name - the name of the gbean from which the class loader should be extracted

Returns:

the class loader associated with the specified GBean

Throws:

GBeanNotFoundException - if the specified GBean is not registered with the kernel

createGBeanName

private GBeanName createGBeanName(javax.management.ObjectName objectName)