This is a program visualization tool aimed at concurrent programs and related issues. The tool itself is mostly language agnostic, and relies on Storm to compile the provided code and provide basic debug information. The generated code is then inspected and instrumented to provide an experience similar to a basic debugger. The tool emphasizes a visual representation of the object hierarchy that is manipulated by the executed program to make it easy to understand how it looks. In particular, a visual representation is beneficial over a text representation since it makes it easier to find shared data that might need to be synchronized in a concurrent program.

As mentioned, the tool is aimed at concurrent programs. Therefore, it allows spawning multiple threads running the same program to see if that affects the program's execution (this is mostly interesting if global variables are used). Furthermore, any spawned threads also appear in the tool, and the user may control them independently to explore possible race conditions or other synchronization errors. If enabled from the menu bar, the tool keeps track of reads and writes to the data structure in order to highlight basic race conditions in addition to deadlocks.

Starting Progvis

To start the tool, download Storm, and click the Progvis file (either Progvis.bat or depending on your system). The main window of Progvis should appear shortly thereafter. You can also start Progvis from the interactive Storm prompt by typing progvis:main, or from the command line by typing Storm -f progvis.main.

Supported languages

In theory, all languages in Storm are supported by Progvis to some extent. As Progvis is a bit intrusive, however, language support varies slightly: