/**
* Checks if the specified step will never yield results.
*
* @param rt root value
* @param s index of step
* @return {@code true} if steps will never yield results
*/
private boolean emptyPath(final Value rt, final int s) {
final Step step = axisStep(s);
if (step == null) return false;
final Axis axis = step.axis;
if (s == 0) {
// first location step:
if (root instanceof CAttr) {
// @.../child:: / @.../descendant::
if (axis == CHILD || axis == DESC) return true;
} else if (root instanceof Root
|| root instanceof CDoc
|| rt != null && rt.type == NodeType.DOC) {
if (axis == SELF || axis == ANCORSELF) {
if (step.test != Test.NOD && step.test != Test.DOC) return true;
} else if (axis == CHILD || axis == DESC) {
if (step.test == Test.DOC || step.test == Test.ATT) return true;
} else if (axis == DESCORSELF) {
if (step.test == Test.ATT) return true;
} else {
return true;
}
}
} else {
// remaining steps:
final Step last = axisStep(s - 1);
if (last == null) return false;
// .../self:: / .../descendant-or-self::
if (axis == SELF || axis == DESCORSELF) {
if (step.test == Test.NOD) return false;
// @.../..., text()/...
if (last.axis == ATTR && step.test.type != NodeType.ATT
|| last.test == Test.TXT && step.test != Test.TXT) return true;
if (axis == DESCORSELF) return false;
// .../self::
final QNm name = step.test.name, lastName = last.test.name;
if (lastName == null
|| name == null
|| lastName.local().length == 0
|| name.local().length == 0) return false;
// ...X/...Y
return !name.eq(lastName);
}
// .../following-sibling:: / .../preceding-sibling::
if (axis == FOLLSIBL || axis == PRECSIBL) return last.axis == ATTR;
// .../descendant:: / .../child:: / .../attribute::
if (axis == DESC || axis == CHILD || axis == ATTR)
return last.axis == ATTR
|| last.test == Test.TXT
|| last.test == Test.COM
|| last.test == Test.PI
|| axis == ATTR && step.test == Test.NSP;
// .../parent:: / .../ancestor::
if (axis == PARENT || axis == ANC) return last.test == Test.DOC;
}
return false;
}
/**
* Returns a new Java function instance.
*
* @param name function name
* @param args arguments
* @param qc query context
* @param sc static context
* @param ii input info
* @return Java function or {@code null}
* @throws QueryException query exception
*/
static JavaMapping get(
final QNm name,
final Expr[] args,
final QueryContext qc,
final StaticContext sc,
final InputInfo ii)
throws QueryException {
final byte[] uri = name.uri();
// check if URI starts with "java:" prefix (if yes, module must be Java code)
final boolean java = startsWith(uri, JAVAPREF);
// rewrite function name: convert dashes to upper-case initials
final String local = camelCase(string(name.local()));
// check imported Java modules
final String path = camelCase(toPath(java ? substring(uri, JAVAPREF.length) : uri));
final ModuleLoader modules = qc.resources.modules();
final Object jm = modules.findImport(path);
if (jm != null) {
final Method meth = getModMethod(jm, path, local, args.length, qc, ii);
if (meth != null) return new JavaModuleFunc(sc, ii, jm, meth, args);
}
// only allowed with administrator permissions
if (!qc.context.user.has(Perm.ADMIN)) return null;
// check addressed class
try {
return new JavaFunc(sc, ii, modules.findClass(path), local, args);
} catch (final ClassNotFoundException ex) {
// only throw exception if "java:" prefix was explicitly specified
if (java) throw FUNCJAVA_X.get(ii, path);
} catch (final Throwable th) {
throw JAVAINIT_X.get(ii, th);
}
// no function found
return null;
}
/**
* Checks if the location path contains steps that will never yield results.
*
* @param stps step array
* @param ctx query context
*/
void voidStep(final Expr[] stps, final QueryContext ctx) {
for (int l = 0; l < stps.length; ++l) {
final Step s = axisStep(l);
if (s == null) continue;
final Axis sa = s.axis;
if (l == 0) {
if (root instanceof CAttr) {
// @.../child:: / @.../descendant::
if (sa == CHILD || sa == DESC) {
ctx.compInfo(WARNDESC, root);
return;
}
} else if (root instanceof Root
|| root instanceof Value && ((Value) root).type == NodeType.DOC
|| root instanceof CDoc) {
if (sa != CHILD
&& sa != DESC
&& sa != DESCORSELF
&& (sa != SELF && sa != ANCORSELF || s.test != Test.NOD && s.test != Test.DOC)) {
ctx.compInfo(WARNDOC, root, sa);
return;
}
}
} else {
final Step ls = axisStep(l - 1);
if (ls == null) continue;
final Axis lsa = ls.axis;
boolean warning = true;
if (sa == SELF || sa == DESCORSELF) {
// .../self:: / .../descendant-or-self::
if (s.test == Test.NOD) continue;
// @.../..., text()/...
warning =
lsa == ATTR && s.test.type != NodeType.ATT
|| ls.test == Test.TXT && s.test != Test.TXT;
if (!warning) {
if (sa == DESCORSELF) continue;
// .../self::
final QNm n0 = ls.test.name;
final QNm n1 = s.test.name;
if (n0 == null || n1 == null || n0.local().length == 0 || n1.local().length == 0)
continue;
// ...X/...Y
warning = !n1.eq(n0);
}
} else if (sa == FOLLSIBL || sa == PRECSIBL) {
// .../following-sibling:: / .../preceding-sibling::
warning = lsa == ATTR;
} else if (sa == DESC || sa == CHILD || sa == ATTR) {
// .../descendant:: / .../child:: / .../attribute::
warning =
lsa == ATTR
|| ls.test == Test.TXT
|| ls.test == Test.COM
|| ls.test == Test.PI
|| sa == ATTR && s.test == Test.NSP;
} else if (sa == PARENT || sa == ANC) {
// .../parent:: / .../ancestor::
warning = ls.test == Test.DOC;
}
if (warning) {
ctx.compInfo(WARNSELF, s);
return;
}
}
}
}