docs: public Processor setOutputDir(final URI output) {
          if (!output.isAbsolute()) {
              throw new IllegalArgumentException("Output directory URI must be absolute: " + output);
          }
          if (!output.getScheme().equals("file")) {
              throw new IllegalArgumentException("Only file scheme allowed as output directory URI: " + output);
          }
          args.put("output.dir", output.toString());
          return this;
      }