Multiple Java installs

[Funkstar]

I have the following installed:
J2SE Runtime Environment Update 4
J2SE Runtime Environment Update 6
Java(TM) 6 Update 3
Java(TM) 6 Update 3

Am I right in assuming I can un-install the first 3 without effecting the last one?

Would save me about 360MB

[Taz]

I would say that there is a possibility that you may cause an application to stop working properly. Perhaps specific apps had a JRE bundled with them which has caused you to have multiple versions? Applications often come bundled with a specific JRE that they have been tested on and may point to that JRE when they start up.

One thing you could check is if the CLASSPATH environment variable is set. If so, this might be because at least one app is using the JRE in the directory specified by the CLASSPATH variable.

Other than that, if you are sure that no apps are using any of the JREs then you should be okay to delete the ones you don't want.

[vinnyT]

You could uninstall the previous versions, but (as Taz pointed out) I did this just recently (like you I wanted my disk space back) and lost use of one of my database apps, not a major problem, but annoying (and bad coding by the Java people.)

[peterb]

Way outside my direct experience - but I thgought an application used the most recent installed version by default.

(The reason I say that it that we recently had an instance of one application that required a lter version of the JRE that was installed, butr another application that would only run with the earlier version - and installing both versions didn't help - both looked at the later ones - but I may be way off in my understanding of the problem)

[Funkstar]

The only time Java is used is on a web page.

Bugger it, the oldest three are going now, I've uninstalled all the other rubish from this laptop. Hopefully it will behave a little better now.

Thanks for the input guys

[this_is_gav]

Worst case should be that you'll have to uninstall that 4th one and then reinstall the latest.

[Bleak]

Yeah I usually uninstall all the old version and just install the latest whenever there's an update.

[mrk]

It's an "update" so I don't understand why it doesn't "update" JAVA instead of leaving so much behind.

I play Yahoo Pool a lot and sometimes get JAVA issues because of this :/