JLog is a Prolog interpreter written in Java that is well suited for educational purposes. It runs as either an Applet or as an Application. It includes built-in source editor, query panels, online help, animation primitives, and a GUI debugger. There is also an API for the jlogic Prolog Engine making it easy to perform Prolog queries from within other programs.
Version 1.2.2 fixes a critical issue with list unification, and an issue with the display of variables in queries. See bug #1108069
This version now uses monospaced fonts for display of source code (easier to read and edit). The Source text area in the Consult pane is now wider in the Applet.
More information, including screenshots, an online demo applet, and release notes are available from: