code: @GET
      @Path("/verifyInjectedOptionalCustomMissing")
      @Produces(MediaType.APPLICATION_JSON)
      public JsonObject verifyInjectedOptionalCustomMissing() {
          boolean pass = false;
          String msg;
          // custom-missing
          Optional<Long> customValue = custom.getValue();
          if(customValue == null) {
              msg = "custom-missing value is null, FAIL";
          }
          else if(!customValue.isPresent()) {
              msg = "custom-missing PASS";
              pass = true;
          }
          else {
              msg = String.format("custom: %s != %s", null, customValue.get());
          }
          JsonObject result = Json.createObjectBuilder()
              .add("pass", pass)
              .add("msg", msg)
              .build();
          return result;
      }
docs: Verify that values exist and that types match the corresponding Claims enum
  @return a series of pass/fail statements regarding the check for each injected claim