Java Issues

[Solarus]

So I've been trying to set up a Tekkit server. I finally solved one problem, only to be hampered by another. I only had Java 6, and upon launch I got an error. I looked it up and found out I needed Java 7. I got it, and stupidly uninstalled the earlier version.

I went to the launcher again (reinstalling the server stuff) and now it's searching for Java 6! I tried reinstalling it, but had some problems with that.

Can anybody help me? I've been trying to figure this out all day.

Thanks,

Solarus.