someNode.appendChild(attr) broken?

[Nobody/Anonymous]

When I attempt to append a new attribute node onto a specific node, I get a
null pointer exception from within jtidy -- Am I not initializing something or
is there a bug? Here is my code:

private void addTarget_blank(Document doc){
NodeList list = doc.getElementsByTagName("a");
for(int i=0; i<list.getLength(); i++){
NamedNodeMap map = list.item(i).getAttributes();
for (int j = 0; j < map.getLength(); j++) {
if(map.getNamedItem("target") == null){
Attr attr = doc.createAttribute("target");
attr.setNodeValue("_blank");
attr.setValue("_blank");
list.item(i).appendChild(attr);
}
}
}
}

[Nobody/Anonymous]

Whoops, I have an extra loop in there, but that aside, the problem persists.

[aditsu]

Can you post the complete stack trace?

[Martin]

Have you tried casting the node to element and using setAttribute(name, value)
instead as a workaround? Could you provide a testcase?