com.quadcap.util.threads.PeriodicScheduler Class Reference

Inheritance diagram for com.quadcap.util.threads.PeriodicScheduler:

Detailed Description

This class acts as a scheduler for periodic tasks, which are named and execute repeatedly with a specified interval.

Each task is a Command object, as used by e.g., StreamWorker.

Two flavors of this class are expressed here -- the first class takes a Stream parameter. When each task becomes ready, the Command object is written to the Stream, and it is presumed that a StreamWorker task will be sitting at the other end of the Stream, executing the Commands that come down the pipe.

The other flavor of this class takes a context argument, which can be any Java object (i.e., this class doesn't ever look at the context.) When each task becomes ready, it is simply executed within the PeriodicScheduler thread.

Author:: Stan Bailes

Definition at line 76 of file PeriodicScheduler.java.

Public Member Functions

PeriodicScheduler (ThreadGroup group, String name, Object obj)

Construct a new PeriodicScheduler which will write Commands to the specified Stream.

void add (String name, Command c, long interval)

Add a new task, with the specified name, action, and interval.

void add (String name, Runnable r, long interval)

Add a new task, with the specified name, action, and interval.

void run ()

Thread method, runs the main scheduler event loop: Get the next task to execute (the active list is sorted by execution time) and wait that long.

int handleInteractiveCommand (String cmd, Vector args)

Handle a debug monitor command directed at this instance.

String toString ()

void terminate ()

Terminate this scheduler.

Package Functions

void remove (ScheduleItem item)

void schedule (ScheduleItem item)

Add the specified schedule item to the queue.

long msUntil (Date d)

How many ms between now and then (d)?

Package Attributes

DList active = new DList()

Stream stream = null

Object context = null

boolean terminate = false

Hashtable schedule = new Hashtable()

Constructor & Destructor Documentation

com.quadcap.util.threads.PeriodicScheduler.PeriodicScheduler ( ThreadGroup group,

String name,

Object obj

)

Construct a new PeriodicScheduler which will write Commands to the specified Stream.

Parameters:

stream the Stream used to write Commands when they become ready.

Definition at line 90 of file PeriodicScheduler.java.

Member Function Documentation

void com.quadcap.util.threads.PeriodicScheduler.add ( String name,

Runnable r,

long interval

)

Add a new task, with the specified name, action, and interval.
The task will NOT be executed 'now'; rather its first execution will be scheduled at time 'now + interval'.

Parameters:

name the name of this task. Any existing task with the same name is replaced by this one.

r the Runnable action associated with this task.

interval the interval (in ms) between invocations of this task.

Definition at line 138 of file PeriodicScheduler.java.
References com.quadcap.util.threads.PeriodicScheduler.active, com.quadcap.util.threads.ScheduleItem.interval, com.quadcap.util.threads.PeriodicScheduler.remove(), com.quadcap.util.threads.ScheduleItem.runnable, and com.quadcap.util.threads.PeriodicScheduler.schedule.

void com.quadcap.util.threads.PeriodicScheduler.add ( String name,

Command c,

long interval

)

Add a new task, with the specified name, action, and interval.
The task will NOT be executed 'now'; rather its first execution will be scheduled at time 'now + interval'.

Parameters:

name the name of this task. Any existing task with the same name is replaced by this one.

c the Command action associated with this task.

interval the interval (in ms) between invocations of this task.

Definition at line 111 of file PeriodicScheduler.java.
References com.quadcap.util.threads.PeriodicScheduler.active, com.quadcap.util.threads.PeriodicScheduler.add(), com.quadcap.util.threads.ScheduleItem.command, com.quadcap.util.threads.ScheduleItem.interval, com.quadcap.util.threads.PeriodicScheduler.remove(), and com.quadcap.util.threads.PeriodicScheduler.schedule.
Referenced by com.quadcap.util.threads.PeriodicScheduler.add().

long com.quadcap.util.threads.PeriodicScheduler.msUntil ( Date d ) [package]

How many ms between now and then (d)?

Parameters:

d then

Returns:
then - now

Definition at line 347 of file PeriodicScheduler.java.
References com.quadcap.util.threads.PeriodicScheduler.msUntil().
Referenced by com.quadcap.util.threads.PeriodicScheduler.msUntil(), and com.quadcap.util.threads.PeriodicScheduler.run().

void com.quadcap.util.threads.PeriodicScheduler.remove ( ScheduleItem item ) [package]

Definition at line 154 of file PeriodicScheduler.java.
References com.quadcap.util.threads.PeriodicScheduler.active, com.quadcap.util.DList.head, com.quadcap.util.DListItem.next, com.quadcap.util.DListItem.obj, com.quadcap.util.threads.PeriodicScheduler.remove(), and com.quadcap.util.DList.unlink().
Referenced by com.quadcap.util.threads.PeriodicScheduler.add(), and com.quadcap.util.threads.PeriodicScheduler.remove().

void com.quadcap.util.threads.PeriodicScheduler.schedule ( ScheduleItem item ) [package]

Add the specified schedule item to the queue.

Parameters:

item the item to schedule

Definition at line 180 of file PeriodicScheduler.java.
References com.quadcap.util.threads.PeriodicScheduler.active, com.quadcap.util.DList.addBefore(), com.quadcap.util.DList.addFront(), com.quadcap.util.threads.ScheduleItem.checkDate(), com.quadcap.util.threads.ScheduleItem.date, com.quadcap.util.DList.head, com.quadcap.util.DListItem.next, com.quadcap.util.DListItem.obj, and com.quadcap.util.threads.PeriodicScheduler.schedule.

void com.quadcap.util.threads.PeriodicScheduler.terminate ( )

Terminate this scheduler.

Definition at line 356 of file PeriodicScheduler.java.
References com.quadcap.util.threads.PeriodicScheduler.active.

String com.quadcap.util.threads.PeriodicScheduler.toString ( )

Definition at line 316 of file PeriodicScheduler.java.
References com.quadcap.util.threads.PeriodicScheduler.active, com.quadcap.util.threads.ScheduleItem.date, com.quadcap.util.DList.head, com.quadcap.util.threads.ScheduleItem.interval, com.quadcap.util.threads.ScheduleItem.isRunning(), com.quadcap.util.threads.ScheduleItem.name, com.quadcap.util.DListItem.next, and com.quadcap.util.DListItem.obj.

Member Data Documentation

Object com.quadcap.util.threads.PeriodicScheduler.context = null [package]

Definition at line 79 of file PeriodicScheduler.java.
Referenced by com.quadcap.util.threads.PeriodicScheduler.run().

Hashtable com.quadcap.util.threads.PeriodicScheduler.schedule = new Hashtable() [package]

Definition at line 81 of file PeriodicScheduler.java.
Referenced by com.quadcap.util.threads.PeriodicScheduler.add(), and com.quadcap.util.threads.PeriodicScheduler.schedule().

Stream com.quadcap.util.threads.PeriodicScheduler.stream = null [package]

Definition at line 78 of file PeriodicScheduler.java.
Referenced by com.quadcap.util.threads.PeriodicScheduler.run().

boolean com.quadcap.util.threads.PeriodicScheduler.terminate = false [package]

Definition at line 80 of file PeriodicScheduler.java.
Referenced by com.quadcap.util.threads.PeriodicScheduler.run().


Public Member Functions
	PeriodicScheduler (ThreadGroup group, String name, Object obj)
	Construct a new PeriodicScheduler which will write Commands to the specified Stream.
void	add (String name, Command c, long interval)
	Add a new task, with the specified name, action, and interval.
void	add (String name, Runnable r, long interval)
	Add a new task, with the specified name, action, and interval.
void	run ()
	Thread method, runs the main scheduler event loop: Get the next task to execute (the active list is sorted by execution time) and wait that long.
int	handleInteractiveCommand (String cmd, Vector args)
	Handle a debug monitor command directed at this instance.
String	toString ()
void	terminate ()
	Terminate this scheduler.
Package Functions
void	remove (ScheduleItem item)
void	schedule (ScheduleItem item)
	Add the specified schedule item to the queue.
long	msUntil (Date d)
	How many ms between now and then (d)?
Package Attributes
DList	active = new DList()
Stream	stream = null
Object	context = null
boolean	terminate = false
Hashtable	schedule = new Hashtable()