配置hibernate.hbm.xml的头部是：
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
配置hibernate.cfg.xml的头部是：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
配置hibernate.hbm.xml与配置hibernate.cfg.xml的头部一点小区别
原文：http://www.cnblogs.com/guanmanying/p/5192943.html