WEB-INF/classes/META-INF/persistence.xml
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0"> <!-- - Specifies the example's persistence unit. --> <persistence-unit name="example"> <class>example.Student</class> <class>example.Course</class> <class>example.Grade</class> <exclude-unlisted-classes/> </persistence-unit> </persistence>