• Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other Pie Elite all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Jeanne Boyarsky
  • Ron McLeod
  • Paul Clapham
  • Liutauras Vilda
Sheriffs:
  • paul wheaton
  • Rob Spoor
  • Devaka Cooray
Saloon Keepers:
  • Stephan van Hulst
  • Tim Holloway
  • Carey Brown
  • Frits Walraven
  • Tim Moores
Bartenders:
  • Mikalai Zaikin

What does it mean by adding parameter "-classic" into java VM?

 
Ranch Hand
Posts: 84
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanx!
 
Ranch Hand
Posts: 1140
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
The Java 2 SDK and Java 2 Runtime Environment contain two implementations of the Java virtual machine.
a) The Java HotSpotTM Client VM
b) The Java 2 Classic VM
The default VM is the HotSpot. When -classic option is used, it invokes the Classic VM.
 
Ranch Hand
Posts: 90
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
In java 1.4.1 isn't such option, instead you
can use:
-Xint
Operate in interpreted-only mode. Compilation to native code is disabled, and all bytecodes are executed by the interpreter. The performance benefits offered by the Java HotSpot Client VM's adaptive compiler will not be present in this mode.
 
Javan Li
Ranch Hand
Posts: 84
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
What 'd difference between classic and HotSpot VM??Thanx!
 
Sheriff
Posts: 9109
12
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hot Spot generally runs your code faster.
 
Ranch Hand
Posts: 15304
6
Mac OS X IntelliJ IDE Chrome
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
HotSpot is what is considered a "Look Ahead" Interpretor. It takes your byte code and takes it down to native code before executing so that it actually executes faster. This instead of interpreting one line at a time and executing that way.
A little simpler than what actually happens, but I believe that is the idea.
 
Greenhorn
Posts: 3
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hmmm,
So is there a difference between the "look ahead" method file and a machine code file?
I mean, are we compiling to the point that there wouldn't be x-platform portability at all?
If so, there are times I would sacrifice the speed...if not, why ever use the classic (or Xint)?
 
reply
    Bookmark Topic Watch Topic
  • New Topic