/**
* Performs the attribute function.
*
* @param ctx query context
* @return iterator
* @throws QueryException query exception
*/
private Iter attribute(final QueryContext ctx) throws QueryException {
final IndexContext ic = new IndexContext(ctx, data(0, ctx), null, true);
final IndexAccess ia = new IndexAccess(input, expr[1], IndexType.ATTRIBUTE, ic);
// return iterator if no name test is specified
if (expr.length < 3) return ia.iter(ctx);
// parse and compile the name test
final Item name = checkNoEmpty(expr[2].item(ctx, input));
final QNm nm = new QNm(checkStr(name, ctx), ctx);
if (!nm.hasPrefix()) nm.uri(ctx.sc.ns.uri(EMPTY));
final NameTest nt = new NameTest(nm, NameTest.Name.STD, true);
// no results expected: return empty sequence
if (!nt.comp(ctx)) return Empty.ITER;
// wrap iterator with name test
return new Iter() {
final NodeIter ir = ia.iter(ctx);
@Override
public ANode next() throws QueryException {
ANode n;
while ((n = ir.next()) != null && !nt.eval(n)) ;
return n;
}
};
}
@Override
public FElem item(final QueryContext ctx, final InputInfo ii) throws QueryException {
final int s = prepare(ctx);
try {
// adds in-scope namespaces
final Atts ns = new Atts();
for (int i = 0; i < nspaces.size(); ++i) {
ns.add(nspaces.name(i), nspaces.string(i));
}
// create and check QName
final QNm nm = qname(ctx, ii);
final byte[] cp = nm.prefix(), cu = nm.uri();
if (eq(cp, XML) ^ eq(cu, XMLURI)) CEXML.thrw(input, cu, cp);
if (eq(cu, XMLNSURI)) CEINV.thrw(input, cu);
if (eq(cp, XMLNS)) CEINV.thrw(input, cp);
// analyze element namespace unless it is "xml"
if (!eq(cp, XML)) {
// request namespace for the specified uri
final byte[] uri = ctx.sc.ns.uri(cp);
// check if element has a namespace
if (nm.hasURI()) {
// add to statically known namespaces
if (!comp && (uri == null || !eq(uri, cu))) ctx.sc.ns.add(cp, cu);
// add to in-scope namespaces
if (!ns.contains(cp)) ns.add(cp, cu);
} else {
// element has no namespace: assign default uri
nm.uri(uri);
}
}
// create child and attribute nodes
final Constr constr = new Constr(ii, ctx).add(expr);
if (constr.errAtt) NOATTALL.thrw(input);
if (constr.errNS) NONSALL.thrw(input);
if (constr.duplAtt != null) (comp ? CATTDUPL : ATTDUPL).thrw(input, constr.duplAtt);
if (constr.duplNS != null) DUPLNSCONS.thrw(input, constr.duplNS);
// create node
final FElem node = new FElem(nm, constr.children, constr.atts, ns);
// add namespaces from constructor
final Atts cns = constr.nspaces;
for (int a = 0; a < cns.size(); ++a) {
addNS(cns.name(a), cns.string(a), ns);
}
// update parent references of attributes and add namespaces
for (int a = 0; a < constr.atts.size(); ++a) {
constr.atts.get(a).parent(node);
final ANode att = constr.atts.get(a);
final QNm qnm = att.qname();
// skip attributes without prefixes or URIs
if (!qnm.hasPrefix() || !qnm.hasURI()) continue;
// skip XML namespace
final byte[] apref = qnm.prefix();
if (eq(apref, XML)) continue;
final byte[] auri = qnm.uri();
final byte[] npref = addNS(apref, auri, ns);
if (npref != null) {
constr.atts.item[a] =
new FAttr(new QNm(concat(npref, COLON, qnm.local()), auri), att.string());
}
}
// add inherited namespaces
final Atts stack = ctx.sc.ns.stack();
for (int a = stack.size() - 1; a >= 0; a--) {
final byte[] pref = stack.name(a);
if (!ns.contains(pref)) ns.add(pref, stack.string(a));
}
// update parent references of children
for (int c = 0; c < constr.children.size(); ++c) {
final ANode child = constr.children.get(c).parent(node);
// add inherited and remove unused namespaces
if (child.type == NodeType.ELM) {
if (ctx.sc.nsInherit) inherit(child, ns);
if (!ctx.sc.nsPreserve) noPreserve(child);
child.optimize();
}
}
// return generated and optimized node
return node.optimize();
} finally {
ctx.sc.ns.size(s);
}
}