2
在執行以下代碼：MalformedURLException的使用文件URI
doc = builder.parse(file);
其中doc是org.w3c.dom.Document和builder一個實例是javax.xml.parsers.DocumentBuilder一個實例，我發現了以下異常：
Exception in thread "main" java.net.MalformedURLException: unknown protocol: c
at java.net.URL.<init>(Unknown Source)
at java.net.URL.<init>(Unknown Source)
at java.net.URL.<init>(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$DTDDriver.dispatch(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(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.DOMParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(Unknown Source)
at javax.xml.parsers.DocumentBuilder.parse(Unknown Source)
at com.acme.ItemToThetaValues.createFiles(ItemToThetaValues.java:47)
它在文件的這一行上窒息：
<!DOCTYPE questestinterop SYSTEM "C:\Program Files\Acme\parsers\acme_full.dtd">
我的機器上沒有出現此錯誤，而用戶正在使用他的機器。我們都使用Sun JRE的第6版。當他在路徑中使用雙反斜槓而不是單反斜槓時，以及使用正斜槓而不是反斜槓時，也會發生此錯誤。
首先，XML是否正確？路徑表達是否正確？其次，爲什麼這個錯誤發生在一臺電腦上，而不是另一臺電腦上？