J2SE Runtime Environment 5.0?

[nganvu]

may I ask what exactely the "J2SE Runtime Environment 5.0" does to someone's PC ( What the purpose of having this file)?
Thanks

[Steve R Jones]

Java 2 Platform, Standard Edition (J2SE) provides a complete environment for applications development on desktops and servers and for deployment in embedded environments. It also serves as the foundation for the Java 2 Platform, Enterprise Edition (J2EE) and Java Web Services. » Read More

http://java.sun.com/j2se/

[Welshjim]

nganvu--Sun offers Java in several versions. Their site is almost incomprehensible as to the differences.
For the casual user of Java, the 1.4.x series seems good enough to allow viewing of Java content on websites. The 1.5 series--also recently started to be called 5.0 to introduce a little more confusion--is for developers. But it will also allow viewing Java content.
You can download either for casual use. And both versions have gone through several levels of Updates, so get those,too.
And as the article provided by Steve R Jones says, then there are enterprise versions, etc. If you are at that level, you probably can understand the differences better than I.
OK, so I rambled on and did not answer your question. Basically some webpages are written with Java code (to allow animations, etc.) You need a Java program on your PC to see the content on those sites. MS used to offer Virtual Machine which performed more or less the same functionality, but due to patent issues, MS no longer supports Virtual Machine or even offers it for new download. However, depending on how old your OS is, you might already have Virtual Machine on your PC. You can test here.
http://www.albany.net/~rubergd/example1.html
If you do not have either version of Java, then you will probably have to get it from Sun. If you do not care to see Java content, then you can just forget about it.
Even a short definition of Java is not easy to understand
http://www.webopedia.com/TERM/J/Java.html
And remember that Java and Javascript are two different things.
http://www.webopedia.com/TERM/J/JavaScript.html

[HAN]

FWIW, I started running 1.5 branch earlier this year with no issues. Made the most sense to me since it is the newest version...

[nganvu]

Wow! I am confused enough
Well, I have a PC with Win XP home edition. After updating to XP SP2 it became WinPro. My PC might come bundled with some kind of Java thing from the manufacturer ( I have not built my own PC yet). Yesterday, I saw a Java icon on the bottom right of the screen , asking me to update the Java. I Did not know what it does.
Thank you for your explainations.
PS: for sure, I had it on my PC along with the Virtual thing from MS. Hopefully they get along

[Welshjim]

nganvu--Did you try the test to see if you have any Java (or Virtual Machine) on your PC? It sounds like you have Sun's Java. You will not get update messages from MS about Virtual Machine. And Sun will not send update messages unless you have Sun Java already installed.
If you are getting an update message, can you just follow instructions and update? Or else go to the site mentioned by Steve R Jones. If you are going to have Java on your PC, you might as well have the latest version.
Yes, the two versions of Java usually get along. You can check IE Tools|Internet Options|Advanced tab|Java to see if you possibly have only one checked as the default version to be used, anyway.
On another subject

I have a PC with Win XP home edition. After updating to XP SP2 it became WinPro

That is not possible, unless you updated to SP2 by using an update (or full) version of WinXP Pro SP2. Updating WinXP Home to SP2 from MS Windows Update or download sites will only give you Windows XP Home SP2.

[nganvu]

welshJim: I might sound stupid, but how to check if I have Sun Java or Virtual Machine?
I went to control panel, then add/remove programs. I found:
Java 2 runtime environment, SEV1.4.2_05
J2SE runtime environment 5.0 update 2
J2SE runtime environment 5.0 update 4

Virtual Machine is nowhere to be found in add/reomove programs.
I need more help.

[General Winters]

http://javatester.org/version.html

[HAN]

I found:
Java 2 runtime environment, SEV1.4.2_05
J2SE runtime environment 5.0 update 2
J2SE runtime environment 5.0 update 4

Check at General Winter's site but I'm going to speculate that the last one will be the one active. Update 4 is the latest version of J2SE 5.0 (as of last weekend anyway!) The earlier two can be uninstalled. (FWIW, I'm pretty sure that 1.4.2_05 had some negative security issues.)

[nganvu]

Thanks. Winters and Han.
I will uninstall the other two and keep only the update 4.
Once again, how to check if I have also the Virtual ....also?
Thanks

[General Winters]

How to check if you have the MS jvm

http://www.java.com/en/download/help/uninstall_msvm.xml

[HAN]

Here is a link to a current "heated" debate on Sun Java vs. MS Virtual Machine. http://www.dslreports.com/forum/rema...flat~days=9999

If you had MSJVM on your PC and removed it, you might find the link listed in the next to the last post on page 3 handy (posted by MorpheusUK). It gives details that the MSJVM removal tool that MS released does not remove a key registry entry. The link gives info on how to go about replacing it with a Sun Java entry. (I tried it and it worked on my XP PC.)

(FWIW, I have not found any of the posts compelling enough to convince me that MSJVM is THE Java to keep and use. It is very outdated and was just security "patched" again by MS in the last 30 days. Not a good thing IMO. My feeling is that if you don't specifically need it, dump it. Just my opinion! )

[HAN]

One last update...

I tried the registry "fix" I noted above on a Win 98SE box and it worked ok on it too. So if you decide to remove MS-JVM, be sure to finish the job by doing the registry "fix"...

[nganvu]

Thank you, guys, for your feedbacks.