hibernate.sourceforge.net Nested exception: hibern

在Configuration.buildSessionFactory中，parse  xxx.hbm.xml的时候，经常抛出UnknowHostException：hibernate.sourceforge.net，而我将DTD换成我本地的地址就可以了，难道一定要写上DTD引用的吗？如果我的server没连在internet上面，要把DTD放在本地，但我如果换了路径，那岂不是要将所有的XML都修改？
异常如下：
org.dom4j.DocumentException: hibernate.sourceforge.net Nested exception: hibernate.sourceforge.net
at org.dom4j.io.SAXReader.read(SAXReader.java:358)
at net.sf.hibernate.cfg.Configuration.addInputStream(Configuration.java:252)
at net.sf.hibernate.cfg.Configuration.addClass(Configuration.java:286)
at dbdemo.HibernateDemo.run(HibernateDemo.java:53)
at dbdemo.HibernateDemo.main(HibernateDemo.java:31)
Nested exception:
java.net.UnknownHostException: hibernate.sourceforge.net
at java.net.InetAddress.getAllByName0(InetAddress.java:591)
at java.net.InetAddress.getAllByName0(InetAddress.java:560)
at java.net.InetAddress.getByName(InetAddress.java:469)
at java.net.Socket.<init>(Socket.java:121)
at sun.net.NetworkClient.doConnect(NetworkClient.java:65)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:361)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:548)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:296)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:306)
at sun.net.www.http.HttpClient.New(HttpClient.java:318)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:466)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:562)
at java.net.URL.openStream(URL.java:826)
at org.apache.xerces.impl.XMLEntityManager.startEntity(XMLEntityManager.java:748)
at org.apache.xerces.impl.XMLEntityManager.startDTDEntity(XMLEntityManager.java:708)
at org.apache.xerces.impl.XMLDTDScannerImpl.setInputSource(XMLDTDScannerImpl.java:258)
at org.apache.xerces.impl.XMLDocumentScannerImpl$DTDDispatcher.dispatch(XMLDocumentScannerImpl.java:833)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:333)
at org.apache.xerces.parsers.StandardParserConfiguration.parse(StandardParserConfiguration.java:525)
at org.apache.xerces.parsers.StandardParserConfiguration.parse(StandardParserConfiguration.java:581)
at org.apache.xerces.parsers.XMLParser.parse(XMLParser.java:147)
at org.apache.xerces.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1158)
at org.dom4j.io.SAXReader.read(SAXReader.java:339)
at net.sf.hibernate.cfg.Configuration.addInputStream(Configuration.java:252)
at net.sf.hibernate.cfg.Configuration.addClass(Configuration.java:286)
at dbdemo.HibernateDemo.run(HibernateDemo.java:53)
at dbdemo.HibernateDemo.main(HibernateDemo.java:31)
MappingException hibernate.sourceforge.net Nested exception: hibernate.sourceforge.net
java.lang.NullPointerException
at dbdemo.HibernateDemo.run(HibernateDemo.java:172)
at dbdemo.HibernateDemo.main(HibernateDemo.java:31)
Exception in thread "main"

Users.hbm.xml：
<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>
    <class
        name="dbdemo.Users"
        table="Users"
        dynamic-update="false"
    >

        <id
            name="userID"
            column="LogonID"
            type="string"
            unsaved-value="any"
        >
            <generator class="assigned">
            </generator>
        </id>

        <property
            name="emailAddress"
            type="string"
            update="true"
            insert="true"
            column="EmailAddress"
        />

        <property
            name="lastLogon"
            type="date"
            update="true"
            insert="true"
            column="LastLogon"
        />

        <property
            name="password"
            type="string"
            update="true"
            insert="true"
            column="Password"
        />

        <property
            name="userName"
            type="string"
            update="true"
            insert="true"
            column="Name"
        />

        <set
            name="contacts"
            table="Contacts"
            lazy="false"
            inverse="false"
            cascade="all"
            sort="unsorted"
        >

              <key
                  column="User_ID"
              />

              <one-to-many
                  class="dbdemo.Contact"
              />
        </set>

        <set
            name="books"
            table="Book_User_Link"
            lazy="false"
            inverse="false"
            cascade="all"
            sort="unsorted"
        >

              <key
                  column="UserID"
              />

              <many-to-many
                  class="dbdemo.Book"
                  column="BookID"
                  outer-join="auto"
              />

        </set>

        <one-to-one
            name="address"
            class="dbdemo.Address"
            cascade="none"
            outer-join="auto"
            constrained="false"
        />

        <!--
            To add non XDoclet property mappings, create a file named
                hibernate-properties-User.xml
            containing the additional properties and place it in your merge dir.
        -->

    </class>

</hibernate-mapping>

如果将文件头换成

<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN"
    "file:///F:/hibernate-test/classes/hibernate-mapping-2.0.dtd">
就可以了。

----------------------------------------------------------------------

org.dom4j.DocumentException: hibernate.sourceforge.net Nested exception: hibernate.sourceforge.net
at org.dom4j.io.SAXReader.read(SAXReader.java(Compiled Code))
at net.sf.hibernate.cfg.Configuration.addInputStream(Configuration.java(Compiled Code))
at org.springframework.orm.hibernate.LocalSessionFactoryBean.afterPropertiesSet(LocalSessionFactoryBean.java:383)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:990)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:275)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:193)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java(Compiled Code))
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java(Compiled Code))
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:230)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:304)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:80)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:65)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java(Compiled Code))
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java(Compiled Code))
at java.lang.reflect.Constructor.newInstance(Constructor.java(Compiled Code))
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:73)

-----------------------------------------------------------------------本机调试时出现的情况：  由于我使用的Hibernate3.0   而 项目中使用的是Hibernate2.0 的所以出现上述错误，映射表要和2.0的一样，特别是DTD表头，望吸取教训，