my suggestions are:

java version:

1.1.7

development kit:

Blackdown.org. ftp://ftp.tux.org/pub/java/JDK-1.1.7/. this kit contains the compiler, interpreter, appletviewer etc.

byte-code compiler:

if you're interested in a fast compiler: Jikes (IBM research) http://www.alphaworks.ibm.com/formula.nsf/toolpreview/9E352B2BFCB64CD5882566D0007083E0. jikes also allows you to make Makefiles. it's one of the best compilers around.

jit:

TYA jit compiler (i haven't used it) ftp://gonzalez.cyberus.ca/pub/Linux/java

great online book:

The Java Tutorial (Sun Microsystems) http://java.sun.com/docs/books/tutorial/

my (Lew) favorite paper book on java:

Java in a Nutshell, O'Reilly It's about 1000x more useful than any other book on java i have seen, especially if you are trying to learn the diff from c/c++ to java. about 50% of the book covers the language and environment and 50% is a reference for the libraries. It's in my office if you want to borrow it.. -lew

IDE:

Emacs-JDE http://sunsite.auc.dk/jde/

some general stuff:

• JavaSignals: catch Linux signals version 0.2 http://interstice.com/~kevinh/projects/javasignals/
• JavaComm for Linux: use Linux serial ports in a platform independent manner http://www.interstice.com/~kevinh/linuxcomm.html the last two seem interesting... some of the links in the pages are down, so i haven't been able to find much about them.