Following is from the J701 Release Highlights and Overview.
The JFE is dead, long live the JFE!
701 is a major release (6 to 7). Minor releases (601 to 602) avoid changes which break applications. Major releases introduce incompatible changes if there is sufficient long term benefit.
701 J Engine (JE - J Language implementation) changes are incremental and compatible.
701 J Front End (JFE) changes are revolutionary!
Previously the primary JFE was based on Jsoftware's proprietary WD (window driver). WD was built on Windows API and was refined and polished over more than 15 years. And for 10 years Unix users had a WD Java port.
701 abandons WD. There is risk as WD was a mature product central in so many ways to J. The replacements are as far from polished as only software version 1 can be.
With your patience and contributions we believe the rough will soon be polished and WD will be just a fond memory. One significant difference is that WD was a closed and proprietary system implemented in C++ and Java. The new JFE's are open and are implemented in J and based on open products and industry standards.
A simple, but far reaching, J Engine change makes it relatively easy to completely write a JFE in J. This has enabled the development of two new J front ends.
The second is JGTK which is based on the GTK+ portable library for creating graphical user interfaces. This is on the bleeding edge of what is possible and will allow the ultimate in power user tools and applications.
Packaging is another area of change. This is largely driven by the great success of JAL (J Application Library). The ability to easily update and extend a system with JAL encouraged us to strip down the installers.
The install for each platform is a minimum system with jconsole and jhs. Use JAL to get jgtk and any addons or updates you need. The minimal install doesn't even include the help included in previous releases. Get help with JAL or just use help at the web site.
The install process for each platform is pretty much unchanged from previous releases.
J has a console interface called jconsole and a GUI interface called jhs. Use jhs for an easier introduction to both standard and new features.
The system includes 3 online books that are introductions: J Primer by Eric Iverson, J for C Programmers by Henry Rich, and Learning J by Roger Stokes. They vary in approach and you can probably benefit from reading all three. Hopefully you will find one which matches your requirements and outlook.
Take the time to read the User Manual chapter J System Overview.
Whether you are new to J or an old hand, it is a good idea to start by exploring the jhs menu. Browse help to get an idea of what is there and how to navigate.
www.jsoftware.com, code.jsoftware.com/wiki, and the J forums are J resources. Take some time and explore J on the web.