Disable DOM DTD validation

setValidating(false) will not prevent DTD validation, but you can set http://apache.org/xml/features/nonvalidating/load-external-dtd feature to false. I think is a Xerces-only feature, though, it may not be recognized by other parsers.

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setValidating(false);
        //factory.setFeature("http://xml.org/sax/features/external-parameter-entities", false); // it doesn't work
        factory.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false);
        DocumentBuilder parser = factory.newDocumentBuilder();
        Document doc = parser.parse(getClass().getResourceAsStream("ennote.xml"));

Typical DTD not found exception stacktrace

java.io.FileNotFoundException: /Users/ecerulm/NetBeansProjects/en4j/NBPlatformApp/DTD/xhtml1-strict.dtd (No such file or directory)
    at java.io.FileInputStream.open(Native Method)
    at java.io.FileInputStream.<init>(FileInputStream.java:106)
    at java.io.FileInputStream.<init>(FileInputStream.java:66)
    at sun.net.www.protocol.file.FileURLConnection.connect(FileURLConnection.java:70)
    at sun.net.www.protocol.file.FileURLConnection.getInputStream(FileURLConnection.java:161)
    at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrentEntity(XMLEntityManager.java:653)
    at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startEntity(XMLEntityManager.java:1315)
    at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startDTDEntity(XMLEntityManager.java:1282)
    at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.setInputSource(XMLDTDScannerImpl.java:283)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.dispatch(XMLDocumentScannerImpl.java:1193)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.next(XMLDocumentScannerImpl.java:1090)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:1003)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:648)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:807)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
    at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:107)
    at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(DOMParser.java:225)
    at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:283)
    at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:124)
    at com.rubenlaguna.en4j.NoteContentViewModule.NoteContentViewTopComponent.resultChanged(NoteContentViewTopComponent.java:141)
...
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