eventmanager.java

hibernate quickly 一书的各章节源代码

package com.manning.hq.ch03;


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

import java.util.List;

/**
 * The EventManager serves to encapsulate the major operations
 * we're going to test for Chapter 3.  This class isn't enterprise
 * ready, but it's complex enough to run through some test cases.
 *
 * @author Nick Heudecker
 * @author Patrick Peak
 */
public class EventManager {

    private SessionFactory factory;

    public EventManager() throws Exception {
        initSessionFactory();
    }

    /**
     * Initialize the SessionFactory instance.
     *
     * @throws Exception
     */
    protected void initSessionFactory() throws Exception {
        factory = new Configuration().configure().
            buildSessionFactory();
    }

    /**
     * Save an Event instance, returning the id of the saved
     * instance.
     *
     * @param event
     * @return Long
     * @throws Exception
     */
    public Long save(Event event) throws Exception {
        Session session = factory.openSession();
        Transaction t = session.beginTransaction();
        Long id = null;
        try {
            session.saveOrUpdate(event);
            t.commit();
            id =  event.getId();
        }
        catch (Exception e) {
            t.rollback();
        }
        finally {
            session.close();
        }
        return id;
    }

    /**
     * Returns a List of Event instances matching a given name.
     *
     * @param name
     * @return List of Event instances, or null if nothing matched.
     * @throws Exception
     */
    public List findByName(String name) throws Exception {
        Session session = factory.openSession();
        List results = null;
        try {
            results = session.find("from Event e where e.name=?", name, Hibernate.STRING);
        }
        finally {
            session.close();
        }
        return results;
    }

}