加载不同位置hibernate包产生的问题

public class AnnotationConfFactory extends ConfFactory {
	private final static Logger logger = Logger.getLogger(AnnotationConfFactory.class);

	public AnnotationConfFactory(String hibernate_cfg_xml) {
		super(hibernate_cfg_xml);
	}

	public void createSessionFactory() {
		try {
			Configuration configuration = null;
			if ((hibernate_cfg_xml != null) && (hibernate_cfg_xml.length() != 0)){
				configuration = new AnnotationConfiguration().configure(hibernate_cfg_xml);
			}else{
				configuration = new AnnotationConfiguration().configure();
			}
			this.sessionFactory = configuration.buildSessionFactory();
		} catch (HibernateException e) {
			logger.error("Hibernate Annotation start error: " + e);
		}

	}
	
}