Class QThreadPoolExecutor

java.lang.Object

org.jpos.q2.QBeanSupport

org.jpos.q2.qbean.QThreadPoolExecutor

All Implemented Interfaces:

Configurable, QBean, QThreadPoolExecutorMBean, QBeanSupportMBean, QPersist

public class QThreadPoolExecutor
extends QBeanSupport
implements QThreadPoolExecutorMBean

A qbean dedicated to thread pool executor creation and registration by Q2 NameRegistrar registry

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_TERMINATION_TIMER	Default XML_CONFIG_ATTR__EXEC_SRV_TERMINATION_TIMER value, in seconds.
static final String	THREAD_POOL_EXECUTOR__QBEAN_PREFIX	Prefix used when registering pooled executors in NameRegistrar.
static final String	XML_CONFIG_ATTR__EXEC_SRV_COREPOOLSIZE	XML attribute setting the executor's core pool size.
static final String	XML_CONFIG_ATTR__EXEC_SRV_TERMINATION_TIMER	XML attribute setting the awaitTermination timeout, in seconds.
static final String	XML_CONFIG_ATTR__EXEC_SRV_TYPE	XML attribute selecting the executor type (fixed, cached, scheduled, single).

Fields inherited from class QBeanSupport

cfg, log, scheduledThreadPoolExecutor

Modifier and Type	Field	Description
protected Configuration	cfg	Configuration applied to this bean by the container.
protected Log	log	Logger associated with this bean.
protected ScheduledThreadPoolExecutor	scheduledThreadPoolExecutor	Lazily-allocated scheduler shared with subclasses; see QBeanSupport.getScheduledThreadPoolExecutor().

Fields inherited from interface QBean

DESTROYED, FAILED, STARTED, STARTING, stateString, STOPPED, STOPPING

Modifier and Type	Field	Description
static final int	DESTROYED	QBean has been destroyed.
static final int	FAILED	QBean has failed.
static final int	STARTED	QBean is running.
static final int	STARTING	QBean is in the process of starting.
static final String[]	stateString	Human-readable names for each QBean state, indexed by state constant.
static final int	STOPPED	QBean is stopped.
static final int	STOPPING	QBean is in the process of stopping.

Constructor Summary

Constructors

Constructor	Description
QThreadPoolExecutor()	Default constructor; no instance state to initialise.

Method Summary

Modifier and Type	Method	Description
int	getActiveCount()	Returns the approximate number of threads that are actively executing tasks.
protected org.jdom2.Attribute	getAttribute(org.jdom2.Element elt, String attrName, boolean mandatory, String errDesc)	Returns a required or optional XML attribute, raising a configuration error with errDesc as context when a mandatory attribute is missing or empty.
long	getCompletedTaskCount()	Returns the approximate total number of tasks that have completed execution.
int	getCorePoolSize()	Returns the core number of threads.
String	getExecSrvType()	Returns the executor service type.
int	getInitialCorePoolSize()	Returns the core pool size requested at configuration time.
long	getKeepAliveTimeMS()	Returns the thread keep-alive time in milliseconds.
int	getLargestPoolSize()	Returns the largest number of threads that have ever simultaneously been in the pool.
int	getMaximumPoolSize()	Returns the maximum allowed number of threads.
int	getPoolSize()	Returns the current number of threads in the pool.
protected String	getRegistrationName()	Returns the NameRegistrar key under which this bean's executor is registered.
long	getTaskCount()	Returns the approximate total number of tasks that have been scheduled for execution.
int	getTerminationTimer()	Returns the await-termination delay in milliseconds.
static ThreadPoolExecutor	getThreadPoolExecutor(String name)	Retrieves a thread pool executor from NameRegistrar given its name.
static <T extends ThreadPoolExecutor> T	getThreadPoolExecutor(String name, Class<T> clazz)	Retrieves a thread pool executor from NameRegistrar given its name and expected class.
protected void	initService()	Handle specific config elements type := "fixed" | "scheduled" | "cached" corePoolSize := integer (required for "fixed" and "scheduled" kinds, optional for "cached" kind)
boolean	isShutdown()	Returns whether this executor has been shut down.
boolean	isTerminated()	Returns whether all tasks have completed following shut down.
boolean	isTerminating()	Returns whether this executor is in the process of terminating after shutdown.
protected void	setExecSrvType(String execSrvType)	Sets the executor type (fixed, cached, scheduled, or single).
protected void	setInitialCorePoolSize(int initialCorePoolSize)	Sets the initial core pool size used when the executor is created.
protected void	setTerminationTimer(int terminationTimer)	Sets the awaitTermination timeout, in seconds.
protected void	startService()	Called during the start lifecycle phase; subclasses may override.
protected void	stopService()	Called during the stop lifecycle phase; subclasses may override.

Methods inherited from class QBeanSupport

addAttr, close, createElement, defaultRealm, destroy, destroyService, getAttrs, getAttrs, getConfiguration, getDump, getFactory, getLoader, getLoaderURLS, getLog, getLogger, getName, getPersist, getProperties, getProperty, getRealm, getScheduledThreadPoolExecutor, getServer, getState, getStateAsString, init, isModified, running, setAttr, setConfiguration, setLogger, setModified, setName, setPersist, setProperty, setRealm, setServer, setState, start, stop

Modifier and Type	Method	Description
protected void	addAttr(org.jdom2.Element e, String name, Object obj, String type)	Appends an <attr> child element with name/type/value to e.
protected void	close(Closeable... closeables)	Closes a sequence of Closeable resources, logging any failures as a warning.
protected org.jdom2.Element	createElement(String name, Class mbeanClass)	Builds a JDOM Element reflecting the bean's persistent attributes, driven by the JavaBean introspection of mbeanClass.
protected String	defaultRealm()	Returns the default realm for this bean; subclasses may override.
void	destroy()	destroy the service
protected void	destroyService()	Called during the destroy lifecycle phase; subclasses may override.
protected Iterator	getAttrs()	Iterates over top-level <attr> children of the persisted element.
protected Iterator	getAttrs(String parent)	Iterates over <attr> children nested under the given parent element name.
Configuration	getConfiguration()	Returns the configuration applied to this bean.
String	getDump()	Returns a textual dump of this bean's state.
QFactory	getFactory()	Returns the QFactory associated with the hosting Q2 server.
QClassLoader	getLoader()	Returns the QClassLoader for this bean.
URL[]	getLoaderURLS()	Returns the URLs registered with the class loader.
Log	getLog()	Returns the Log used by this bean.
String	getLogger()	Returns the logger name.
String	getName()	Returns the bean name.
org.jdom2.Element	getPersist()	Returns the persistent configuration element for this QBean.
protected Iterator	getProperties(String parent)	Iterates over <property> children nested under the given parent element name.
protected String	getProperty(Iterator props, String name)	Returns the value of the named property from an iterator of <property> elements.
String	getRealm()	Returns the logging realm.
protected ScheduledThreadPoolExecutor	getScheduledThreadPoolExecutor()	Lazily creates and returns a ScheduledThreadPoolExecutor for use by subclasses.
Q2	getServer()	Returns the Q2 server instance.
int	getState()	Returns the current state of this QBean.
String	getStateAsString()	Returns the current state as a human-readable string.
void	init()	init the service
boolean	isModified()	Returns true if this QBean's configuration has been modified since last save.
boolean	running()	Indicates whether this bean is currently starting or running.
protected void	setAttr(Iterator attrs, String name, Object obj)	Updates the value of the named attribute within an iterator of <attr> elements.
void	setConfiguration(Configuration cfg)	Configures this object with the supplied Configuration.
void	setLogger(String loggerName)	Sets the logger by name.
void	setModified(boolean modified)	Marks this bean's persistent state as modified or in sync.
void	setName(String name)	Sets the bean name.
void	setPersist(org.jdom2.Element persist)	Sets the persistent configuration element.
protected void	setProperty(Iterator props, String name, String value)	Updates the value attribute of the named property within an iterator of <property> elements.
void	setRealm(String realm)	Sets the logging realm.
void	setServer(Q2 server)	Sets the Q2 server instance for this QBean.
void	setState(int state)	Sets the lifecycle state of this bean.
void	start()	start the service
void	stop()	stop the service

Methods inherited from class Object

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

Field Details

THREAD_POOL_EXECUTOR__QBEAN_PREFIX

public static final String THREAD_POOL_EXECUTOR__QBEAN_PREFIX

Prefix used when registering pooled executors in NameRegistrar.

See Also:

• Constant Field Values

XML_CONFIG_ATTR__EXEC_SRV_TYPE

public static final String XML_CONFIG_ATTR__EXEC_SRV_TYPE

XML attribute selecting the executor type (fixed, cached, scheduled, single).

See Also:

• Constant Field Values

XML_CONFIG_ATTR__EXEC_SRV_COREPOOLSIZE

public static final String XML_CONFIG_ATTR__EXEC_SRV_COREPOOLSIZE

XML attribute setting the executor's core pool size.

See Also:

• Constant Field Values

XML_CONFIG_ATTR__EXEC_SRV_TERMINATION_TIMER

public static final String XML_CONFIG_ATTR__EXEC_SRV_TERMINATION_TIMER

XML attribute setting the awaitTermination timeout, in seconds.

See Also:

• Constant Field Values

DEFAULT_TERMINATION_TIMER

public static final int DEFAULT_TERMINATION_TIMER

Default XML_CONFIG_ATTR__EXEC_SRV_TERMINATION_TIMER value, in seconds.

See Also:

• Constant Field Values

Constructor Details

QThreadPoolExecutor

public QThreadPoolExecutor()

Default constructor; no instance state to initialise.

Method Details

initService

protected void initService()
                    throws Exception

Handle specific config elements type := "fixed" | "scheduled" | "cached" corePoolSize := integer (required for "fixed" and "scheduled" kinds, optional for "cached" kind)

Overrides:

initService in class QBeanSupport

Throws:

Exception - on error

startService

protected void startService()
                     throws Exception

Description copied from class: QBeanSupport

Called during the start lifecycle phase; subclasses may override.

Overrides:

startService in class QBeanSupport

Throws:

Exception - on error

stopService

protected void stopService()
                    throws Exception

Description copied from class: QBeanSupport

Called during the stop lifecycle phase; subclasses may override.

Overrides:

stopService in class QBeanSupport

Throws:

Exception - on error

getRegistrationName

protected String getRegistrationName()

Returns the NameRegistrar key under which this bean's executor is registered.

Returns:

the registration name (prefix concatenated with this bean's configured name)

getAttribute

protected org.jdom2.Attribute getAttribute(org.jdom2.Element elt,
 String attrName,
 boolean mandatory,
 String errDesc)
                                    throws ConfigurationException

Returns a required or optional XML attribute, raising a configuration error with errDesc as context when a mandatory attribute is missing or empty.

Parameters:

elt - source element

attrName - attribute name to look up

mandatory - if true, missing/empty attributes raise an exception

errDesc - human-readable description appended to the error message

Returns:

the attribute, or null when not mandatory and absent

Throws:

ConfigurationException - if the attribute is mandatory and missing/empty

getThreadPoolExecutor

public static ThreadPoolExecutor getThreadPoolExecutor(String name)
                                                throws NameRegistrar.NotFoundException

Retrieves a thread pool executor from NameRegistrar given its name.

Parameters:

name - bean name (without the THREAD_POOL_EXECUTOR__QBEAN_PREFIX prefix)

Returns:

the registered ThreadPoolExecutor

Throws:

NameRegistrar.NotFoundException - if no executor is registered under that name

getThreadPoolExecutor

public static <T extends ThreadPoolExecutor> T getThreadPoolExecutor(String name,
 Class<T> clazz)
                                                              throws NameRegistrar.NotFoundException

Retrieves a thread pool executor from NameRegistrar given its name and expected class.

Type Parameters:

T - expected concrete executor type

Parameters:

name - bean name (without the THREAD_POOL_EXECUTOR__QBEAN_PREFIX prefix)

clazz - expected executor class

Returns:

the registered executor, narrowed to T

Throws:

NameRegistrar.NotFoundException - if no executor of the expected class is registered under that name

getExecSrvType

public String getExecSrvType()

Description copied from interface: QThreadPoolExecutorMBean

Returns the executor service type.

Specified by:

getExecSrvType in interface QThreadPoolExecutorMBean

Returns:

executor service type

getTerminationTimer

public int getTerminationTimer()

Description copied from interface: QThreadPoolExecutorMBean

Returns the await-termination delay in milliseconds.

Specified by:

getTerminationTimer in interface QThreadPoolExecutorMBean

Returns:

await termination delay

getActiveCount

public int getActiveCount()
                   throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the approximate number of threads that are actively executing tasks.

Specified by:

getActiveCount in interface QThreadPoolExecutorMBean

Returns:

approximate number of threads that are actively executing tasks

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getCompletedTaskCount

public long getCompletedTaskCount()
                           throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the approximate total number of tasks that have completed execution.

Specified by:

getCompletedTaskCount in interface QThreadPoolExecutorMBean

Returns:

the approximate total number of tasks that have completed execution.

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getCorePoolSize

public int getCorePoolSize()
                    throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the core number of threads.

Specified by:

getCorePoolSize in interface QThreadPoolExecutorMBean

Returns:

returns the core number of threads.

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getKeepAliveTimeMS

public long getKeepAliveTimeMS()
                        throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the thread keep-alive time in milliseconds.

Specified by:

getKeepAliveTimeMS in interface QThreadPoolExecutorMBean

Returns:

the thread keep-alive time, which is the amount of time (in milliseconds) which threads in excess of the core pool size may remain idle before being terminated

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getLargestPoolSize

public int getLargestPoolSize()
                       throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the largest number of threads that have ever simultaneously been in the pool.

Specified by:

getLargestPoolSize in interface QThreadPoolExecutorMBean

Returns:

the largest number of threads that have ever simultaneously been in the pool.

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getMaximumPoolSize

public int getMaximumPoolSize()
                       throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the maximum allowed number of threads.

Specified by:

getMaximumPoolSize in interface QThreadPoolExecutorMBean

Returns:

the maximum allowed number of threads.

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getPoolSize

public int getPoolSize()
                throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the current number of threads in the pool.

Specified by:

getPoolSize in interface QThreadPoolExecutorMBean

Returns:

the current number of threads in the pool.

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getTaskCount

public long getTaskCount()
                  throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns the approximate total number of tasks that have been scheduled for execution.

Specified by:

getTaskCount in interface QThreadPoolExecutorMBean

Returns:

the approximate total number of tasks that have been scheduled for execution

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

isShutdown

public boolean isShutdown()
                   throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns whether this executor has been shut down.

Specified by:

isShutdown in interface QThreadPoolExecutorMBean

Returns:

true if this executor has been shut down.

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

isTerminated

public boolean isTerminated()
                     throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns whether all tasks have completed following shut down.

Specified by:

isTerminated in interface QThreadPoolExecutorMBean

Returns:

true if all tasks have completed following shut down

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

isTerminating

public boolean isTerminating()
                      throws NameRegistrar.NotFoundException

Description copied from interface: QThreadPoolExecutorMBean

Returns whether this executor is in the process of terminating after shutdown.

Specified by:

isTerminating in interface QThreadPoolExecutorMBean

Returns:

true if this executor is in the process of terminating after shutdown or shutdownNow but has not completely terminated.

Throws:

NameRegistrar.NotFoundException - if the executor cannot be found in the name registrar

getInitialCorePoolSize

public int getInitialCorePoolSize()

Returns the core pool size requested at configuration time.

Returns:

the initially configured core pool size

setExecSrvType

protected void setExecSrvType(String execSrvType)

Sets the executor type (fixed, cached, scheduled, or single).

Parameters:

execSrvType - the new executor type

setInitialCorePoolSize

protected void setInitialCorePoolSize(int initialCorePoolSize)

Sets the initial core pool size used when the executor is created.

Parameters:

initialCorePoolSize - core pool size

setTerminationTimer

protected void setTerminationTimer(int terminationTimer)

Sets the awaitTermination timeout, in seconds.

Parameters:

terminationTimer - timeout used during shutdown