The Java Data Mining API (JDM) is the first attempt to create a standard Java
API to access data-mining tools from Java applications.  JDM  promises to
bring to data mining what JDBC brought to databases, and to make data mining a
new and useful part of an enterprise Java developer's tool chest. This article
introduces basic data-mining concepts, and illustrates sample JDM code to
model customer behavior. 
http://www.artima.com/lejava/articles/data_mining.htmlWhat do you think of the Java Data Mining API?