struts2 的错误信息： java.net.UnknownHostException: struts.apache.org

错误：

aused by: struts.apache.org - [unknown location]
        at com.opensymphony.xwork2.util.DomHelper.parse(DomHelper.java:115)
        at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadConfigurationFiles(XmlConfigurationProvider.java:885)
        ... 34 more
Caused by: java.net.UnknownHostException: struts.apache.org
        at java.net.PlainSocketImpl.connect(Unknown Source)
        at java.net.Socket.connect(Unknown Source)
        at java.net.Socket.connect(Unknown Source)
        at sun.net.NetworkClient.doConnect(Unknown Source)
        at sun.net.www.http.HttpClient.openServer(Unknown Source)
        at sun.net.www.http.HttpClient.openServer(Unknown Source)
        at sun.net.www.http.HttpClient.<init>(Unknown Source)
        at sun.net.www.http.HttpClient.New(Unknown Source)
        at sun.net.www.http.HttpClient.New(Unknown Source)
        at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(Unknown Source)
        at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
        at sun.net.www.protocol.http.HttpURLConnection.connect(Unknown Source)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
        at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrentEntity(Unknown Source)
        at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startEntity(Unknown Source)
        at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startDTDEntity(Unknown Source)
        at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.setInputSource(Unknown Source)
        at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDispatcher.dispatch(Unknown Source)
        at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
        at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
        at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
        at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
        at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
        at javax.xml.parsers.SAXParser.parse(Unknown Source)
        at com.opensymphony.xwork2.util.DomHelper.parse(DomHelper.java:113)
        ... 35 more
2011-2-9 10:16:53 org.apache.catalina.core.StandardContext start
严重: Error filterStart
2011-2-9 10:16:53 org.apache.catalina.core.StandardContext start
严重: Context [/Arms_Collect] startup failed due to previous errors
2011-2-9 10:16:53 org.apache.catalina.core.ApplicationContext log
信息: Closing Spring root WebApplicationContext

解决办法：

就是因为断网了，不能download DTD了所以就报错，解决方法是：
根据DTD中的这个http://struts.apache.org/dtds/struts-2.0.dtd链接将struts-2.0.dtd文件下载到本地硬盘上，然后将DTD中的http://struts.apache.org/dtds/struts-2.0.dtd链接替换成，struts-2.0.dtd文件在硬盘上的路径即可。

具体：

将 struts.xml   中的 <!DOCTYPE struts PUBLIC

         "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
         " http://struts.apache.org/dtds/struts-2.0.dtd ">  

改为：

<!DOCTYPE struts PUBLIC

         "Apache SoftWare Foundation//DTD Struts Configuration 2.0//EN"

         "D:/Anther-hlep-lib-jar/struts-2.0.dtd">

注解：D:/Anther-hlep-lib-jar/struts-2.0.dtd   为struts-2.0.dtd 在我本地纸盘的路径