/**
* Gets the specified method from a query module.
*
* @param mod query module object
* @param path path of the module
* @param name method name
* @param arity number of arguments
* @param qc query context
* @param ii input info
* @return method if found, {@code null} otherwise
* @throws QueryException query exception
*/
private static Method getModMethod(
final Object mod,
final String path,
final String name,
final long arity,
final QueryContext qc,
final InputInfo ii)
throws QueryException {
// find method with identical name and arity
Method meth = null;
for (final Method m : mod.getClass().getMethods()) {
if (m.getName().equals(name) && m.getParameterTypes().length == arity) {
if (meth != null) throw JAVAAMBIG_X.get(ii, "Q{" + path + '}' + name + '#' + arity);
meth = m;
}
}
if (meth == null) throw FUNCJAVA_X.get(ii, path + ':' + name);
// check if user has sufficient permissions to call the function
Perm perm = Perm.ADMIN;
final QueryModule.Requires req = meth.getAnnotation(QueryModule.Requires.class);
if (req != null) perm = Perm.get(req.value().name());
if (!qc.context.user.has(perm)) return null;
// Add module locks to QueryContext.
final QueryModule.Lock lock = meth.getAnnotation(QueryModule.Lock.class);
if (lock != null) {
for (final String read : lock.read()) qc.readLocks.add(DBLocking.MODULE_PREFIX + read);
for (final String write : lock.write()) qc.writeLocks.add(DBLocking.MODULE_PREFIX + write);
}
return meth;
}
/**
* 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;
}