@Override
public NodeIter iter(final QueryContext ctx) throws QueryException {
final Value v = checkCtx(ctx);
if (!v.type.isNode()) NODESPATH.thrw(input, AxisStep.this, v.type);
final AxisIter ai = axis.iter((ANode) v);
final NodeCache nc = new NodeCache();
for (ANode n; (n = ai.next()) != null; ) if (test.eval(n)) nc.add(n.finish());
// evaluate predicates
for (final Expr p : preds) {
ctx.size = nc.size();
ctx.pos = 1;
int c = 0;
for (int n = 0; n < nc.size(); ++n) {
ctx.value = nc.get(n);
final Item i = p.test(ctx, input);
if (i != null) {
// assign score value
nc.get(n).score(i.score());
nc.item[c++] = nc.get(n);
}
ctx.pos++;
}
nc.size(c);
}
return nc;
}
/**
* Builds a sequence of elements from a query's result set.
*
* @param rs result set
* @return sequence of elements <tuple/> each of which represents a row from the result set
* @throws QueryException query exception
*/
private NodeCache buildResult(final ResultSet rs) throws QueryException {
try {
final ResultSetMetaData metadata = rs.getMetaData();
final int columnCount = metadata.getColumnCount();
final NodeCache rows = new NodeCache();
while (rs.next()) {
final NodeCache columns = new NodeCache();
for (int k = 1; k <= columnCount; k++) {
// For each row add column values as children
final String label = metadata.getColumnLabel(k);
final Object value = rs.getObject(label);
// Null values are ignored
if (value != null) {
// Column name
final FAttr columnName = new FAttr(Q_NAME, token(label));
final NodeCache attr = new NodeCache();
attr.add(columnName);
// Column value
final FTxt columnValue = new FTxt(token(value.toString()));
final NodeCache ch = new NodeCache();
ch.add(columnValue);
// Element <sql:column name='...'>...</sql:column>
columns.add(new FElem(Q_COLUMN, ch, attr, NS_SQL, null));
}
}
rows.add(new FElem(Q_ROW, columns, null, NS_SQL, null));
}
return rows;
} catch (final SQLException ex) {
throw SQLEXC.thrw(input, ex.getMessage());
}
}
@Override
public Iter iter(final QueryContext ctx) throws QueryException {
final Value cv = ctx.value;
final long cs = ctx.size;
final long cp = ctx.pos;
try {
Value r = root != null ? ctx.value(root) : cv;
if (!cache
|| citer == null
|| lvalue.type != NodeType.DOC
|| r.type != NodeType.DOC
|| !((ANode) lvalue).is((ANode) r)) {
lvalue = r;
citer = new NodeCache().random();
if (r != null) {
final Iter ir = ctx.iter(r);
while ((r = ir.next()) != null) {
ctx.value = r;
iter(0, citer, ctx);
}
} else {
ctx.value = null;
iter(0, citer, ctx);
}
citer.sort();
} else {
citer.reset();
}
return citer;
} finally {
ctx.value = cv;
ctx.size = cs;
ctx.pos = cp;
}
}
/**
* Recursive step iterator.
*
* @param l current step
* @param nc node cache
* @param ctx query context
* @throws QueryException query exception
*/
private void iter(final int l, final NodeCache nc, final QueryContext ctx) throws QueryException {
// cast is safe (steps will always return a {@link NodIter} instance
final NodeIter ni = (NodeIter) ctx.iter(steps[l]);
final boolean more = l + 1 != steps.length;
for (ANode node; (node = ni.next()) != null; ) {
if (more) {
ctx.value = node;
iter(l + 1, nc, ctx);
} else {
ctx.checkStop();
nc.add(node);
}
}
}
/**
* Adds children of a sub node.
*
* @param ch child nodes
* @param nc node cache
*/
protected final void addDesc(final AxisMoreIter ch, final NodeCache nc) {
for (ANode n; (n = ch.next()) != null; ) {
nc.add(n.finish());
addDesc(n.children(), nc);
}
}