for (int i = 1; i < args.length; i++) {
     if ("fill_form".equals(args[i])) {
         config.formInputStream = System.in;
         i++;
         if (!"-".equals(args[i])) {
             throw new RuntimeException("Missing \"-\" after fill_form operation.");
         }
     } else if ("output".equals(args[i])) {
         i++;
         if (!"-".equals(args[i])) {
             throw new RuntimeException("Missing \"-\" after output operation.");
         }
     } else if ("flatten".equals(args[i])) {
         config.flatten = true;
     } else {
         throw new RuntimeException("Unknown operation: " + args[i]);
     }
 }

Drop-in, блять, replacement for pdftk. Он, вообще-то, не три, а целых девятнадцать операций выполняет! Мудаки.