@Override
    public boolean isDeclared(int index) {
        if (index < 0 || index >= attributeCount) {
            throw new ArrayIndexOutOfBoundsException();
        }
        String type = parser.getAttributeType(elementName, getQName(index));
        return (type != null);
    }
@return false unless the attribute was declared in the DTD.
@throws java.lang.ArrayIndexOutOfBoundsException
            When the supplied index does not identify an attribute.
src/nu/validator/gnu/xml/aelfred2/SAXDriver.java