code: public static Info inviteUserToEnterprise(BoxAPIConnection api, String userLogin, String enterpriseID) {
  
          URL url = INVITE_CREATION_URL_TEMPLATE.build(api.getBaseURL());
          BoxJSONRequest request = new BoxJSONRequest(api, url, "POST");
  
          JsonObject body = new JsonObject();
  
          JsonObject enterprise = new JsonObject();
          enterprise.add("id", enterpriseID);
          body.add("enterprise", enterprise);
  
          JsonObject actionableBy = new JsonObject();
          actionableBy.add("login", userLogin);
          body.add("actionable_by", actionableBy);
  
          request.setBody(body);
          BoxJSONResponse response = (BoxJSONResponse) request.send();
          JsonObject responseJSON = JsonObject.readFrom(response.getJSON());
  
          BoxInvite invite = new BoxInvite(api, responseJSON.get("id").asString());
          return invite.new Info(responseJSON);
      }
docs: Invite a user to an enterprise.
  @param api the API connection to use for the request.
  @param userLogin the login of the user to invite.
  @param enterpriseID the ID of the enterprise to invite the user to.
  @return the invite info.