java.net.MalformedURLException: This exception has no message.

java.net.MalformedURLException
	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$PrologDriver.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
	at org.jdom.input.SAXBuilder.build(SAXBuilder.java:489)
	at org.movsim.input.XmlReaderSimInput$1.run(XmlReaderSimInput.java:289)
	at java.security.AccessController.doPrivileged(Native Method)
	at org.movsim.input.XmlReaderSimInput.getDocument(XmlReaderSimInput.java:271)
	at org.movsim.input.XmlReaderSimInput.readAndValidateXmlFromFileName(XmlReaderSimInput.java:241)
	at org.movsim.input.XmlReaderSimInput.<init>(XmlReaderSimInput.java:111)
	at org.movsim.input.XmlReaderSimInput.parse(XmlReaderSimInput.java:77)
	at org.movsim.simulator.Simulator.initialize(Simulator.java:112)
	at org.movsim.simulator.Simulator.loadScenarioFromXml(Simulator.java:208)
	at org.movsim.viewer.graphics.TrafficCanvas.setupTrafficScenario(TrafficCanvas.java:263)
	at org.movsim.viewer.ui.AppFrame.<init>(AppFrame.java:81)
	at org.movsim.viewer.App.main(App.java:63)
Caused by: java.lang.NullPointerException
	... 30 more