com.prosyst.mprm.backend.event.scheduler

Interface EventGenerator

public interface EventGenerator

Interface for defining event generators in the mprm framework.

Since:

05/03/2004

Version:

1.1

Author:

Alexander Alexandrov, Jordan Simeonov

Method Summary

Modifier and Type	Method and Description
int	getDayOfMonth() Returns the day of month on which an event is fired
long	getDelayTolerance() Returns the permissible delay tolerance
java.util.Date	getEndTime() Returns the end time for this event generator (null denotes indefinitely).
java.lang.Object	getEventData() Returns the event data associated with this event generator.
java.lang.String	getEventType() Returns the event type of the generated events
java.lang.String	getId() Returns the identifier of this event generator
long	getPeriod() Returns the period between 2 successive events.
java.util.Date	getStartTime() Returns the start time for this event generator
boolean	isFixedRate() Returns whether this event generator is a fixed-rate.
boolean	isStarted() Checks if this event generator has been started
Enumerator	previousEvents() Deprecated. this method is no longer supported. Its current implementation returns an empty enumerator.
void	setDayOfMonth(int dayOfMonth) Sets the day of month on which an event is fired
void	setDelayTolerance(long delayInterval) Sets the permissible delay form firing an event by this generator.
void	setEndTime(java.util.Date endTime) Sets the end time for this event generator (null denotes indefinitely).
void	setEventData(java.lang.Object data) Sets the event data associated with this event generator.
void	setFixedRate(boolean fixedRate) In fixed-rate execution, each execution is scheduled relative to the scheduled start time.
void	setPeriod(long period) Sets the period between 2 successive events
void	setStartTime(java.util.Date startTime) Sets the start time for this event generator
void	setStartTimeAfter(int millis) Sets the start time for this event generator relative to the current time
void	setTimeSequence(java.lang.String customTimeSequenceName) Sets the time sequence used by this event generator.
void	start() Starts this event generator.

Method Detail

getId

java.lang.String getId()
                throws ManagementException

Returns the identifier of this event generator

Returns:

the identifier of this event generator

Throws:

ManagementException - If no id has been set

getEventType

java.lang.String getEventType()

Returns the event type of the generated events

Returns:

the event type of the generated events

getEventData

java.lang.Object getEventData()
                       throws ManagementException

Returns the event data associated with this event generator. May be null.

Returns:

the event data associated with this event generator

Throws:

ManagementException - if on-demand construction of the data object fails

setEventData

void setEventData(java.lang.Object data)
           throws ManagementException

Sets the event data associated with this event generator. May be null.

Parameters:

data - the event data associated with this event generator

Throws:

ManagementException - if this generator has been started

getStartTime

java.util.Date getStartTime()

Returns the start time for this event generator

Returns:

the start time for this event generator

setStartTime

void setStartTime(java.util.Date startTime)
           throws ManagementException

Sets the start time for this event generator

Parameters:

startTime - the start time for this event generator (null denotes right now)

Throws:

ManagementException - if this generator has been started

setStartTimeAfter

void setStartTimeAfter(int millis)
                throws ManagementException

Sets the start time for this event generator relative to the current time

Parameters:

millis - the start time for this event generator will be the current time plus the specified amount of milliseconds.

Throws:

ManagementException - if this generator has been started

getEndTime

java.util.Date getEndTime()

Returns the end time for this event generator (null denotes indefinitely).

Returns:

the end time for this event generator (null denotes indefinitely)

setEndTime

void setEndTime(java.util.Date endTime)
         throws ManagementException

Sets the end time for this event generator (null denotes indefinitely).

Parameters:

endTime - the end time for this event generator (null denotes indefinitely).

Throws:

ManagementException - if this generator has been started

getPeriod

long getPeriod()
        throws ManagementException

Returns the period between 2 successive events.

Returns:

the period between 2 successive events in milliseconds.

Throws:

ManagementException - if this is not a periodical event

setPeriod

void setPeriod(long period)
        throws ManagementException

Sets the period between 2 successive events

Parameters:

period - the period between 2 successive events in milliseconds

Throws:

ManagementException - if this generator has been started

setFixedRate

void setFixedRate(boolean fixedRate)
           throws ManagementException

In fixed-rate execution, each execution is scheduled relative to the scheduled start time. If an execution is delayed for any reason (such as temporary stopping of the mPRM or the system is too busy), two or more executions will occur in rapid succession to "catch up." Fixed-rate execution is appropriate for recurring activities that are sensitive to absolute time, such as ringing a chime every hour on the hour, or running scheduled maintenance every day at a particular time. Finally, fixed-rate execution is appropriate for scheduling multiple repeating timer tasks that must remain synchronized with respect to one another.

The opposite of fixed-rate is the fixed-delay execution. In fixed-delay execution, each execution is scheduled relative to the actual execution time of the previous execution. If an execution is delayed for any reason subsequent executions will be delayed as well.

The default behaviour of periodical generators defined by this service is fixed-delay. This method enables definining of fixed-rate schedulres by invoking it with true parameter.

Generators defined by day-of-mount are always fixed-rate and this method does not effect them.

Parameters:

fixedRate - true sets this generator as fixed-rate, false sets it as fixed-delay (the default).

Throws:

ManagementException - if the generator is already started.

isFixedRate

boolean isFixedRate()

Returns whether this event generator is a fixed-rate.

Returns:

true if the generator is a fixed-rate, false otherwise.

See Also:

setFixedRate(boolean fixedRate)

setDelayTolerance

void setDelayTolerance(long delayInterval)
                throws ManagementException

Sets the permissible delay form firing an event by this generator. If firing of an event delays more then the specified by this method time, the event will be skipped at all. The delay tolerance may be defined only for fixed-delay generators and is useful when the periodical task associated with generator must be executed in a particular absolute time or not executed at all. By default the permissible delay interval is equals to the period, i.e. it only ensures that several sequential events are not overlapped.

Parameters:

delayInterval - permissible delay interval in milliseconds.

Throws:

ManagementException - if the generator is already started.

getDelayTolerance

long getDelayTolerance()

Returns the permissible delay tolerance

Returns:

the permissible delay tolerance in milliseconds.

See Also:

setDelayTolerance(long delayInterval)

getDayOfMonth

int getDayOfMonth()
           throws ManagementException

Returns the day of month on which an event is fired

Returns:

the day of month on which an event is fired

Throws:

if - this is not a monthly event

ManagementException

setDayOfMonth

void setDayOfMonth(int dayOfMonth)
            throws ManagementException

Sets the day of month on which an event is fired

Parameters:

dayOfMonth - the day of month on which an event is fired

Throws:

ManagementException - if this generator has been started

start

void start()
    throws ManagementException

Starts this event generator. No changes can be done once the event generator is started. If the generator had been already started, this method has no effect.

Throws:

ManagementException - if this generator cannot be started

isStarted

boolean isStarted()

Checks if this event generator has been started

Returns:

true if this event generator has already been started

previousEvents

Enumerator previousEvents()
                   throws ManagementException

Deprecated. this method is no longer supported. Its current implementation returns an empty enumerator.

Returns the previously generated events by this event generator

Returns:

Enumerator of the previos events

Throws:

ManagementException - if the previous events cannot be obtained

setTimeSequence

void setTimeSequence(java.lang.String customTimeSequenceName)
              throws ManagementException

Sets the time sequence used by this event generator. It must be registred as a service in the mPRM framework.

Parameters:

customTimeSequenceName - the name under which the time sequence for this event generator is registred in the framework

Throws:

ManagementException - if an error occurs.