Implementations Java-Based
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JavaLog - Experimental Prolog interpreter in Java, mixing Logic and OO paradigms.
Jinni 2000 (Java INference Engine and Networked Interactor) - A fast multi-threaded, networking and GUI enabled Prolog compiler, extensible through a Reflection based Java interface.
JIP - Java Internet Prolog is a Prolog Java-compatible interpreter. JDK1.1- and Edinburgh Prolog-compliant this Prolog version allows code written in Prolog to be run in any Java applet or application and Java methods to be called in any Prolog code.
JLog - A Prolog interpreter, written in Java, that is well suited for educational purposes. It works as both an application and as an applet.
jProlog - Experimental Prolog to Java compiler, running on JDK 1.0.2 and higher.
MINERVA - Implementation of ISO Prolog in 100% Java. Extensible with any Java class. Callable as servlet, applet, standalone, or Java class library. Includes XML parser and generator. [Commercial]
Prolog+CG - Java implementation of Prolog plus the Conceptual Graphs of John Sowa. Object oriented extensions also included. [Open source, LGPL]
tuProlog - A Java-based light-weight Prolog for Internet applications and infrastructures, developed at DEIS - Universitá di Bologna. Released under GNU Library or Lesser General Public License.
W-Prolog - This simple interpreter for a Prolog-like language is written in Java. Although not fast the implementation is extremely portable and can be run as an applet under Java-capable web browsers. Help build the largest human-edited directory on the web.