Implementing the Business Tier with Session Beans - Java EE 6 Development with NetBeans 7 - page 257

After clicking on Finish , the session beans are created and placed in the package we
specified.
All of the generated session bean extends AbstractFacade , an abstract class that
is also generated by the Session Beans for Entity Classes wizard. This abstract
class contains a number of methods that allow us to perform CRUD ( Create , Read ,
Update , Delete ) operations on our entities.
package com.ensode.ejbdao.sessionbeans;
import java.util.List;
import javax.persistence.EntityManager;
public abstract class AbstractFacade<T> {
private Class<T> entityClass;
public AbstractFacade(Class<T> entityClass) {
this.entityClass = entityClass;
}
protected abstract EntityManager getEntityManager();
public void create(T entity) {
getEntityManager().persist(entity);
}