You can usually work from pseudo-code to Java. Try a book like Russell and Norvig
Artificial intelligence : a modern approach / Stuart J. Russell and Peter Norvig ; contributing writers, John F. Canny ... [et al.].
Edition 2nd ed.
Series Prentice Hall series in artificial intelligence
Publisher Upper Saddle River, N.J. ; [Great Britain] : Prentice Hall, c2003.
Bib Id 401542
ISBN 0130803022
Physical details xxviii, 1080p : ill. ; 26 cm.
Subject Artificial intelligence.
Notes Previous ed.: 1995.
Includes bibliographical references and index.
See if you can read an extract on Amazon or borrow a copy. If I remember correctly the examples are in such a form that they can easily be converted to Java. Round here, the AI people seem to use LISP, and the Games AI chaps use C, and if it can be written in C it can probably be written in Java.