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Hello,

I would like to write stand-alone application which would download some
files from network every x hrs (specified by the user). I think I would
do it that, that user would just specify the time and minimalize it (it
will be minimalized or I will decide to put it to systray) and then app
every x hrs will wake up and do its job.

How can I do it without slowing a lot OS (processor/memory)? I was
thinking about threads and wait/sleep function but not know if it is
effective method. What do you think?!?

Regards, mark

wrote:
>
> I would like to write stand-alone application which would download some
> files from network every x hrs (specified by the user). I think I would
> do it that, that user would just specify the time and minimalize it (it
> will be minimalized or I will decide to put it to systray) and then app
> every x hrs will wake up and do its job.
>
> How can I do it without slowing a lot OS (processor/memory)? I was
> thinking about threads and wait/sleep function but not know if it is
> effective method. What do you think?!?
>
You don't say what your target OS is or if you want to write a OS you're
running on or if you want to write something that's OS-agnostic so its
difficult to give specific advice.

Personally, I'd do it with cron because then there are no overheads at
all. However, I do run Linux....


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Hello,

> You don't say what your target OS is or if you want to write a OS you're
> running on or if you want to write something that's OS-agnostic so its
> difficult to give specific advice.

It is going to be MS Windows.

Regards, mark

wrote:
> Hello,
>
>> You don't say what your target OS is or if you want to write a OS you're
>> running on or if you want to write something that's OS-agnostic so its
>> difficult to give specific advice.
>
> It is going to be MS Windows.
>
Have you considered writing the application so it does the transfers you
need and then quits and running it under the control of the Windows
Scheduler?

Tis way you get a simple application and there's already a GUI (supplied
by MS) that can control when it gets run.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

wrote:
> Hello,
>
>> You don't say what your target OS is or if you want to write a OS you're
>> running on or if you want to write something that's OS-agnostic so its
>> difficult to give specific advice.
>
> It is going to be MS Windows.
>
> Regards, mark
>

Yes, ditto to what Martin said. Much better to use the OS features than
to try to do everything yourself.

On Windows 2000 (mine), there's a control panel for this:

Start->Programs->Accessories->System Tools->Scheduled Tasks

Encourage the user to place your app here. This provides effectively 0%
overhead, just like cron. I don't think there's any way you can provide
that. Just having the JVM up at all is a pretty large overhead, if it's
going to be doing nothing except expiring a counter every 24 hours.

Also, think about other paradigms. If you are updating another app,
consider having it check for updates whenever its run.