I discovered JPA 2.0 Criteria API today and want to learn it. Just went through some examples and try to do a hands on. I have a table fruit with columns:
Basic tutorial of criteria API can be found at http://download.oracle.com/javaee/6/tutorial/doc/gjivm.html.
Examples can be found at http://www.altuure.com/2010/09/23/jpa-criteria-api-by-samples-part-i/ , also check part 2.