@Override
    public void setEntityResolver(EntityResolver resolver) {
        if (resolver instanceof EntityResolver2) {
            resolver2 = (EntityResolver2) resolver;
        } else {
            resolver2 = null;
        }
        if (resolver == null) {
            resolver = base;
        }
        entityResolver = resolver;
    }
<b>SAX1, SAX2</b>: Set the entity resolver for this parser.

@param resolver
src/nu/validator/gnu/xml/aelfred2/SAXDriver.java