presto-parser/src/main/java/io/prestosql/sql/tree/RenameSchema.java/RenameSchema/RenameSchema
class RenameSchema:    private RenameSchema(Optional<NodeLocation> location, QualifiedName source, Identifier target)
    {
        super(location);
        this.source = requireNonNull(source, "source is null");
        this.target = requireNonNull(target, "target is null");
    }