Subject:
|
Re: RCX and Java
|
Newsgroups:
|
lugnet.robotics
|
Date:
|
Tue, 4 May 1999 20:10:12 GMT
|
Original-From:
|
John A. Tamplin <JAT@LIVEONTHENET.COMsaynotospam>
|
Viewed:
|
4182 times
|
| |
|
|
On Tue, 4 May 1999, Ola Liljedahl wrote:
> Aren't robots real time systems?
> Isn't the RCX meant to be a component in such real time systems?
>
> Java (as implemented by current virtual machines) is NOT suitable
> as a platform for building real time systems. The implementation of
> garbage collection is not deterministic and may take a very long
> time to execute. You Emacs users out there should recognise the problem...
>
> We should make the distinction between real time systems and embedded
> systems. Java is fine for embedded systems with no real time requirements.
>
> In my line of business I see some Java being used in real time systems.
> But never for real time purposes, only for low priority (as regards to
> real time properties) operation and maintenance.
I doubt anyone is considering using the RCX with any OS/language in a hard
real-time system. The original firmware nor any of the replacements make
the proper guarantees required for such a system (ie, a deadline-based
scheduler), and I have not heard anyone suggest that such a system should
be implemented.
You can write Java code that avoids garbage collection, basically you dump
the immutable object concept (ie, the String class creates a new String
object when anything is changed) and instead pass in the object for the
result of a computation.
John A. Tamplin Traveller Information Services
jat@LiveOnTheNet.COM 2104 West Ferry Way
256/705-7007 - FAX 256/705-7100 Huntsville, AL 35801
--
Did you check the web site first?: http://www.crynwr.com/lego-robotics
|
|
Message is in Reply To:
 | | RCX and Java
|
| Aren't robots real time systems? Isn't the RCX meant to be a component in such real time systems? Java (as implemented by current virtual machines) is NOT suitable as a platform for building real time systems. The implementation of garbage (...) (27 years ago, 4-May-99, to lugnet.robotics)
|
67 Messages in This Thread:
  
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|
