〔Java Web 开发典型模块大全〕第八章聊天室模块，范例测试时，发现执行MessagesAction.java 之loginRoom method 时，执行Document feedDoc = builder.build(fileURL);，出现以下错误，请专家帮忙解决，谢谢
上线用户：mr
java.net.MalformedURLException: unknown protocol: c
        at java.net.URL.<init>(URL.java:574)
        at java.net.URL.<init>(URL.java:464)
        at java.net.URL.<init>(URL.java:413)
        at gnu.xml.aelfred2.XmlParser.pushURL(XmlParser.java:3414)
        at gnu.xml.aelfred2.XmlParser.doParse(XmlParser.java:159)
        at gnu.xml.aelfred2.SAXDriver.parse(SAXDriver.java:320)
        at gnu.xml.aelfred2.XmlReader.parse(XmlReader.java:294)
        at org.jdom.input.SAXBuilder.build(SAXBuilder.java:453)
        at org.jdom.input.SAXBuilder.build(SAXBuilder.java:891)
        at com.wgh.MessagesAction.loginRoom(MessagesAction.java:152)
        at com.wgh.MessagesAction.doPost(MessagesAction.java:33)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
        at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
        at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
        at java.lang.Thread.run(Thread.java:619)