Java: How to prevent ‘systemId’ in EntityResolver#resolveEntity(String publicId, String systemId) from being absolutized to current working directory


I want to parse the following XML document to resolve all entities in it:

 <!DOCTYPE doc SYSTEM 'mydoc.dtd'>

My EntityResolver is supposed to fetch the external entity with the given system ID from the database and then do the resolution, see below for an illustration:

 private static class MyEntityResolver
    public InputSource resolveEntity(String publicId, String systemId)
        throws SAXException, IOException
        // At this point, systemId is always absolutized to the current working directory, 
        // even though the XML document specified it as relative.
        // E.g. "file:///H:/mydoc.dtd" instead of just "mydoc.dtd"
        // Why???  How can I prevent this???

        SgmlEntity entity = findEntityFromDatabase(systemId);
        InputSource is = new InputSource(new ByteArrayInputStream(entity.getContents()));
        return is;

I tried both using DOM (DocumentBuilder) and SAX (XMLReader), set the entity resolver to MyEntityResolver (i.e. setEntityResolver(new MyEntityResolver())), but systemId in MyEntityResolver#resolveEntity(String publicId, String systemId) is always being absolutized to the current working directory.

I also tried calling setFeature("", false);, but that didn't help anything.

So how can I achieve what I wanted?


Best Solution

Apparently, there is another interface called EntityResolver2 which is the extension of the old EntityResolver. (Talk about confusing names!)

Anyway, I found that EntityResolver2 achieved what I wanted, that is, it does not make any changes to the systemId, so it will always exactly be what was specified in the XML document.