jGRASP is a lightweight development environment, created specifically to provide automatic generation of software visualizations to improve the comprehensibility of software.
jGRASP is implemented in Java, and runs on all platforms with a Java Virtual Machine (Java version 1.5 or higher). jGRASP produces Control Structure Diagrams (CSDs) for Java, C, C++, Objective-C, Python, Ada, and VHDL; Complexity Profile Graphs (CPGs) for Java and Ada; UML class diagrams for Java; and has dynamic object viewers and a viewer canvas that work in conjunction with an integrated debugger and workbench for Java. The viewers include a data structure identifier mechanism which recognizes objects that represent traditional data structures such as stacks, queues, linked lists, binary trees, and hash tables, and then displays them in an intuitive textbook-like presentation view.
Has an apparently serious problem but I found a fix for it: PROBLEM: Can't write any code at all! When I click in the programming window ("CSD" window), cursor doesn't select the window and nothing comes up when I type. FIX : Have to go to File > Escape Virtual Desktop to be able to write any code. No idea why because the window is supposed to be built in. Aside from that it appears to be able to create and run a whole project online which is a functionality that I can't seem to find anywhere else.