Bongo was by far the most advanced user interface toolkit and editor for Java of its time. It had a HyperCard-like GUI editor AND an interactive script editor that let you build and edit applications and user interfaces while they were running, just like HyperCard, instead of recompiling and restarting every time you made a change.

https://people.apache.org/~jim/NewArchitect/webtech/1997/10/...

>Feel the Beat with Marimba's Bongo

>By Chris Baron

>In 1996, four programmers from the original Java-development team left Sun to form Marimba and produce industrial-strength Java-development tools for user interface and application administration. Bongo, one of Marimba's two shipping products, allows developers to create either a Java-application interface or a standalone Java-based application called a "presentation." A Bongo presentation resembles a HyperCard stack -- it allows developers to quickly create an application with a sophisticated user interface, but without the tedious programming of directly coding in Java or C/C++. Bongo's nonprogramming, visual approach makes it ideal for producing simple applications that don't involve a lot of processing, such as product demonstrations, user-interface prototypes, and training applications. Bongo is fully integrated with Castanet, Marimba's other product, a technology for remotely installing and updating Java applications.

https://www.amazon.com/Official-Marimba-Guide-Bongo-Goodman/...

>Official Marimba Guide to Bongo, by Danny Goodman