public void lookupOperatorOverloads(
final SqlIdentifier opName,
SqlFunctionCategory category,
SqlSyntax syntax,
List<SqlOperator> operatorList) {
if (syntax != SqlSyntax.FUNCTION) {
return;
}
final Collection<Function> functions = getFunctionsFrom(opName.names);
if (functions.isEmpty()) {
return;
}
operatorList.addAll(
Collections2.transform(
functions,
new com.google.common.base.Function<Function, SqlOperator>() {
public SqlOperator apply(Function function) {
return toOp(opName, function);
}
}));
}
private Collection<Function> getFunctionsFrom(List<String> names) {
final List<Function> functions2 = Lists.newArrayList();
final List<? extends List<String>> schemaNameList;
if (names.size() > 1) {
// If name is qualified, ignore path.
schemaNameList = ImmutableList.of(ImmutableList.<String>of());
} else {
OptiqSchema schema = getSchema(defaultSchema);
if (schema == null) {
schemaNameList = ImmutableList.of();
} else {
schemaNameList = schema.getPath();
}
}
for (List<String> schemaNames : schemaNameList) {
OptiqSchema schema = getSchema(Iterables.concat(schemaNames, Util.skipLast(names)));
if (schema != null) {
final String name = Util.last(names);
functions2.addAll(schema.getFunctions(name, true));
}
}
return functions2;
}