org.opennms.core.tasks

Class Task

java.lang.Object

org.opennms.core.tasks.Task

Direct Known Subclasses:

AsyncTask, ContainerTask, SyncTask

public abstract class Task
extends Object

BaseTask

Version:

$Id: $

Author:

brozow

Constructor Summary

Constructors

Constructor and Description
Task(DefaultTaskCoordinator coordinator, ContainerTask<?> parent) Constructor for Task.

Method Summary

Modifier and Type	Method and Description
void	addDependent(Task dependent) Adds dependent as a dependent of this task.
void	addPrerequisite(Task prereq) Add's prereq as a Prerequisite of this task.
protected void	completeSubmit() This method exists to allow a task to have no processing
protected void	doSubmit() This method submits a task to be executed and is called when all dependencies are completed for that task This method should place a runnable on an executor or submit the task in some other way so that it will run as soon as possible.
DefaultTaskCoordinator	getCoordinator() getCoordinator
TaskMonitor	getMonitor() getMonitor
boolean	isFinished() This task's run method has completed
boolean	isScheduled() This task has be sent to the TaskCoordinator to be run
protected void	markTaskAsCompleted() markTaskAsCompleted
protected void	postSchedule() postSchedule
protected void	preSchedule() preSchedule
void	schedule() This is called to add the task to the queue of tasks that can be considered to be runnable
protected void	submitRunnable(Runnable runnable, String preferredExecutor) submitRunnable
String	toString() toString
void	waitFor() Wait for this task to complete.
boolean	waitFor(long timeout, TimeUnit unit) Wait for this task to complete or until a timeout occurs.

Methods inherited from class java.lang.Object

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

Constructor Detail

Task

public Task(DefaultTaskCoordinator coordinator,
            ContainerTask<?> parent)

Constructor for Task.

Parameters:

coordinator - a DefaultTaskCoordinator object.

parent - a ContainerTask object.

Method Detail

getCoordinator

public DefaultTaskCoordinator getCoordinator()

getCoordinator

Returns:

a DefaultTaskCoordinator object.

getMonitor

public TaskMonitor getMonitor()

getMonitor

Returns:

a TaskMonitor object.

doSubmit

protected void doSubmit()

This method submits a task to be executed and is called when all dependencies are completed for that task This method should place a runnable on an executor or submit the task in some other way so that it will run as soon as possible. Tasks that have no processing to be done may override completeSubmit to notify the Task coordinator that the task is done.

completeSubmit

protected void completeSubmit()

This method exists to allow a task to have no processing

schedule

public void schedule()

This is called to add the task to the queue of tasks that can be considered to be runnable

preSchedule

protected void preSchedule()

preSchedule

postSchedule

protected void postSchedule()

postSchedule

isFinished

public boolean isFinished()

This task's run method has completed

Returns:

a boolean.

isScheduled

public boolean isScheduled()

This task has be sent to the TaskCoordinator to be run

Returns:

a boolean.

addPrerequisite

public void addPrerequisite(Task prereq)

Add's prereq as a Prerequisite of this task. In other words... this taks cannot run until prereq was been complted.

Parameters:

prereq - a Task object.

addDependent

public void addDependent(Task dependent)

Adds dependent as a dependent of this task. So dependent will not be able to run until this task has been completed.

Parameters:

dependent - a Task object.

waitFor

public void waitFor()
             throws InterruptedException,
                    ExecutionException

Wait for this task to complete. The current thread will block until this task has been completed.

Throws:

InterruptedException - if any.

ExecutionException - if any.

waitFor

public boolean waitFor(long timeout,
                       TimeUnit unit)
                throws InterruptedException

Wait for this task to complete or until a timeout occurs. If the timeout elapses, then false is returned.

Parameters:

timeout - a long.

unit - a TimeUnit object.

Throws:

InterruptedException - if any.

markTaskAsCompleted

protected void markTaskAsCompleted()

markTaskAsCompleted

submitRunnable

protected void submitRunnable(Runnable runnable,
                              String preferredExecutor)

submitRunnable

Parameters:

runnable - a Runnable object.

preferredExecutor - a String object.

toString

public String toString()

toString

Overrides:

toString in class Object

Returns:

a String object.