配置hibernate时出错原因及解决方案

问题1   hibernate.cfg.xml配置文件

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC"-//Hibernate/Hibernate Configuration DTD 3.0//EN""http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=UTF-8</property>
<property name="connection.username">root</property>
<property name="connection.password">123456</property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">none</property>
<mapping class="/testhibernate/src/org/hibernate/Student"/> <!-- 配置Student类名的路径 -->
</session-factory>
</hibernate-configuration>
出错信息：

Exception in thread "main" org.hibernate.MappingException: Unable to load class [ /testhibernate/src/org/hibernate/Student] declared in Hibernate configuration <mapping/> entry
at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:2221)
at org.hibernate.cfg.Configuration.parseSessionFactory(Configuration.java:2169)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2149)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:2102)
at org.hibernate.cfg.Configuration.configure(Configuration.java:2017)
at org.hibernate.Main.main(Main.java:14)
Caused by: java.lang.ClassNotFoundException: /testhibernate/src/org/hibernate/Student
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.hibernate.internal.util.ReflectHelper.classForName(ReflectHelper.java:192)
at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:2218)
... 5 more
解决方案：

1.hibernate.cfg.xml放在src目录下

2.<mapping class="/testhibernate/src/org/hibernate/Student"/>
类文件写错，不能用"/",应该用" . "    <mapping class="org.hibernate.Student" />

这个问题解决之后出现了另一个问题：加载数据库驱动时出错

问题2

Exception in thread "main" org.hibernate.service.classloading.spi.ClassLoadingException: Specified JDBC Driver com.mysql.jdbc.Driver could not be loaded
at org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:111)
at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:85)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:184)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:156)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.buildJdbcConnectionAccess(JdbcServicesImpl.java:223)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:89)
at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:85)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:184)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:156)
at org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1827)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1785)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1870)
at org.hibernate.Main.main(Main.java:16)
Caused by: org.hibernate.service.classloading.spi.ClassLoadingException: Unable to load class [com.mysql.jdbc.Driver]
at org.hibernate.service.classloading.internal.ClassLoaderServiceImpl.classForName(ClassLoaderServiceImpl.java:151)
at org.hibernate.service.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:106)
... 12 more
Caused by: java.lang.ClassNotFoundException: Could not load requested class : com.mysql.jdbc.Driver
at org.hibernate.service.classloading.internal.ClassLoaderServiceImpl$AggregatedClassLoader.findClass(ClassLoaderServiceImpl.java:318)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.hibernate.service.classloading.internal.ClassLoaderServiceImpl.classForName(ClassLoaderServiceImpl.java:148)
... 13 more

解决方案：忘记导入连接数据库的jar包了，导入之后就ok了
mysql-connector-java-5.1.6.jar