com.dpslink.base.util

Class ScheduledTask

java.lang.Object

com.dpslink.base.util.ScheduledTask

All Implemented Interfaces:

java.io.Serializable, java.lang.Runnable

Direct Known Subclasses:

AdmSendMassEmail.ScheduledMessage, LogCleaner, UpdateAdminContacts

public abstract class ScheduledTask
extends java.lang.Object
implements java.lang.Runnable, java.io.Serializable

An abstract scheduled task definition. Defines functionality which is common to all server scheduled tasks.

A scheduled task is submitted to the FIFO thread queue wherein the task could potentially be stacked in line behind other queue entries. The task therefore might not execute at the exact scheduled time but could be delayed momentarily while waiting for its turn in the queue.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.concurrent.ScheduledFuture<?>	ivFuture The task's scheduled future.
private java.lang.String	ivId The task's id.
private boolean	ivIsBusy A flag indicating if the task is busy.
private boolean	ivIsCanceled A flag indicating if the task has been canceled.
private java.lang.String	ivName The task's name.
private long	ivRerun The task's interval between repeated executions (milliseconds).
private static long	serialVersionUID The class' serialization version id.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ScheduledTask() The constructor for the abstract scheduled task.

Method Summary

Modifier and Type	Method and Description
void	cancel() Instructs the scheduled task that it should end its processing as soon as possible.
boolean	equals(java.lang.Object obj) Compares the given object to this object and determines if the two are equal.
protected abstract void	executeTask() Executes the task's processing.
java.util.concurrent.ScheduledFuture<?>	getFuture() Returns the task's scheduled future.
java.lang.String	getId() Returns the task's id.
java.lang.String	getName() Returns the task's name.
java.util.Date	getNextExecution() Returns the task's next execution time.
long	getRerun() Returns the task's interval between repeated executions (milliseconds).
boolean	isBusy() Answers if the task is currently busy.
boolean	isCanceled() Answers if the task has been canceled.
void	run() Runs the scheduled task.
void	setFuture(java.util.concurrent.ScheduledFuture<?> value) Sets the task's scheduled future.
void	setId(java.lang.String value) Sets the task's id.
void	setName(java.lang.String value) Sets the task's name.
void	setRerun(long value) Sets the task's interval between repeated executions (milliseconds).

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

The class' serialization version id.

See Also:

Constant Field Values

ivId

private java.lang.String ivId

The task's id.

ivName

private java.lang.String ivName

The task's name.

ivRerun

private long ivRerun

The task's interval between repeated executions (milliseconds).

ivFuture

private java.util.concurrent.ScheduledFuture<?> ivFuture

The task's scheduled future.

ivIsBusy

private boolean ivIsBusy

A flag indicating if the task is busy.

ivIsCanceled

private boolean ivIsCanceled

A flag indicating if the task has been canceled.

Constructor Detail

ScheduledTask

protected ScheduledTask()

The constructor for the abstract scheduled task.

Method Detail

equals

public boolean equals(java.lang.Object obj)

Compares the given object to this object and determines if the two are equal. Equality is based on task id.

Overrides:

equals in class java.lang.Object

Parameters:

obj - (Object) The object to compare with this object.

Returns:

boolean - true if the specified object is equal to this object, otherwise false.

getId

public java.lang.String getId()

Returns the task's id.

Returns:

String - The task's id.

setId

public void setId(java.lang.String value)

Sets the task's id.

Parameters:

value - (String) The task's id.

getName

public java.lang.String getName()

Returns the task's name.

Returns:

String - The task's name.

setName

public void setName(java.lang.String value)

Sets the task's name.

Parameters:

value - (String) The task's name.

getRerun

public long getRerun()

Returns the task's interval between repeated executions (milliseconds).

Returns:

long - The task's repeat interval.

setRerun

public void setRerun(long value)

Sets the task's interval between repeated executions (milliseconds).

Parameters:

value - (long) The task's repeat interval.

getFuture

public java.util.concurrent.ScheduledFuture<?> getFuture()

Returns the task's scheduled future.

Returns:

ScheduledFuture - The task's scheduled future.

setFuture

public void setFuture(java.util.concurrent.ScheduledFuture<?> value)

Sets the task's scheduled future.

Parameters:

value - (ScheduledFuture) The task's scheduled future.

getNextExecution

public java.util.Date getNextExecution()

Returns the task's next execution time.

Returns:

Date - The task's next execution time.

isBusy

public boolean isBusy()

Answers if the task is currently busy.

Returns:

boolean - true if busy, otherwise false.

isCanceled

public boolean isCanceled()

Answers if the task has been canceled.

Returns:

boolean - true if canceled, otherwise false.

cancel

public void cancel()

Instructs the scheduled task that it should end its processing as soon as possible. Subclasses should not override this method.

run

public void run()

Runs the scheduled task. Invoked by the Runnable interface. Subclasses should not override this method.

Specified by:

run in interface java.lang.Runnable

executeTask

protected abstract void executeTask()

Executes the task's processing. Automatically invoked when the task's scheduled execution time has occurred. Subclasses should frequently check isCanceled and attempt to gracefully end processing as quickly as possible.