inheritancedemo.java

hibernate_tutorial经典教程

package tutorial.inheritance.tableperconcreteclass;

import java.util.Iterator;
import java.util.List;

import net.sf.hibernate.HibernateException;
import net.sf.hibernate.Session;
import net.sf.hibernate.SessionFactory;
import net.sf.hibernate.Transaction;
import net.sf.hibernate.cfg.Configuration;

public class InheritanceDemo {
	public static void main(String[] args) {
		try {
			new InheritanceDemo();
		} catch(HibernateException he) {
			he.printStackTrace();
		}
	}
	
	public InheritanceDemo() throws HibernateException {
		Configuration config = new Configuration();
		// add the classes you want to persist
		// make sure the mapping files are on the classpath
		config.addClass(Superclass.class);
		config.addClass(Subclass.class);
		
		SessionFactory sf = config.buildSessionFactory();
		
		Session sess = sf.openSession();
		Transaction tx = null;
		try {
			tx = sess.beginTransaction();
			
			Superclass sup = new Superclass();
			sup.setName("abstract class property");
			sup.setSuperName("superclass property");
			sess.save(sup);
			
			Subclass sub = new Subclass();
			sub.setName("abstract class property");
			sub.setSuperName("superclass property");
			sub.setSubName("subclass property");
			sess.save(sub);
		
			tx.commit();
		} catch (HibernateException e) {
		    if (tx!=null) tx.rollback();
		    throw e;
		}
		finally {
		    sess.close();
		}
		sess = sf.openSession();
		tx = null;
		try {
		    tx = sess.beginTransaction();
		    List pets = sess.find("from " + AbstractClass.class.getName());
		    for (Iterator it = pets.iterator(); it.hasNext();) {
				Superclass sc = (Superclass) it.next();
				System.out.println("Class loaded from DB: " + sc.getClass().getName());
			}
		    tx.commit();
		}
		catch (HibernateException e) {
		    if (tx!=null) tx.rollback();
		    throw e;
		}
		finally {
		    sess.close();
		}
	}
}