How is GCJ different from Sun Java?

[Ernest L. Williams Jr.]

Hi,


Can someone explain what is the gcj in the GCC software?
How is it different from Sun Java?

Does gcj need a jvm? Does the jvm come from GNU?

Can we mix and match java libraries from SUN and GNU?
Does gcj have a good graphics library (e.g. swing)?

Is gcj completely compliant with SUN's definition of java?

All of these questions were generated when I started running "Native
Eclipse" on Fedora Core 4.



Thanks,
Ernesto