Last week, we had the author of TDD for a Shopping Website LiveProject. Friday at 11am Ranch time, Steven Solomon will be hosting a live TDD session just for us. See for the agenda and registration link
  • 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
  • Paul Clapham
  • Ron McLeod
  • Jeanne Boyarsky
  • Tim Cooke
Sheriffs:
  • Liutauras Vilda
  • paul wheaton
  • Henry Wong
Saloon Keepers:
  • Tim Moores
  • Tim Holloway
  • Stephan van Hulst
  • Carey Brown
  • Frits Walraven
Bartenders:
  • Piet Souris
  • Himai Minh

JRE VS JVM

 
Ranch Hand
Posts: 31
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
hi all
sorry for asking the following crazy question

JDK : development evironoment which is superset of all
JRE : set of runtime classes subset of JDK
JVM : intrepreter which depends of OS for conversion of byte code to HW understable code.subset of JRE.

why does sun provide JRE for each operating system..isnt JRE same for any OS? why not they just supply JVM for different problems.

please let me know..
raj
 
(instanceof Sidekick)
Posts: 8791
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I'd bet most of the JRE is pure Java and platform independent. But parts of it rely on underlying bits in the OS. Look through some of the DLLs in the JRE/bin and see if you can guess their purpose. I see some for awt, fonts, sounds, instruments (midi?), io. Those are the beasties that must be different for each OS.

I guess we could say the JVM has platform-dependent code to run all the compiled byte codes and the JRE has platform dependent code built in Java. Does that sound reasonable?
 
kumm redd
Ranch Hand
Posts: 31
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
hi stan
nice to see reply from you..hmmm your arguement seems to be interesting , so can i would like to ask you the following

1. why dont separate JVM and JRE into two components instead of having JVM subset of JRE,so that only JVM can be distrubuted for each OS instead of entire JRE?

2.JRE = "JVM" + X(all the remaining)
so does JVM use anything thats avaialable in X?

3. i hope that all the run time libraries such as (java.lang and etc ) are available as part of JRE,why should they be separated for each OS.they can be distrubuted with same version nr for all OS's .
I think its enough if we distrubute only JVM for each OS? wat do you think?

4. does JVM uses any API available in X to convert bytecode to hardware understandable code?

sorry if i am wrong..
just wanted to know
reddy
 
Ranch Hand
Posts: 5093
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I'm pretty certain that Sun internally has separate codebases for the platform dependent and platform independent parts.
Packaging them together as a single installer makes it a lot easier for people to install a JVM though.

I've a hard enough time telling people how to install a program that's a single download/exe. Wouldn't want to have to babysit them through installing something that requires several steps, each of which requiring data from the previous step to work correctly.
 
Ranch Hand
Posts: 158
Java
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I think you should post this topic into

http://java.sun.com/

You will get the best reply ever.
 
What do you have in that there bucket? It wouldn't be a tiny ad by any chance ...
Free, earth friendly heat - from the CodeRanch trailboss
https://www.kickstarter.com/projects/paulwheaton/free-heat
reply
    Bookmark Topic Watch Topic
  • New Topic