code: public void marshall(App app, ProtocolMarshaller protocolMarshaller) {
  
          if (app == null) {
              throw new SdkClientException("Invalid argument passed to marshall(...)");
          }
  
          try {
              protocolMarshaller.marshall(app.getAppId(), APPID_BINDING);
              protocolMarshaller.marshall(app.getAppArn(), APPARN_BINDING);
              protocolMarshaller.marshall(app.getName(), NAME_BINDING);
              protocolMarshaller.marshall(app.getTags(), TAGS_BINDING);
              protocolMarshaller.marshall(app.getDescription(), DESCRIPTION_BINDING);
              protocolMarshaller.marshall(app.getRepository(), REPOSITORY_BINDING);
              protocolMarshaller.marshall(app.getPlatform(), PLATFORM_BINDING);
              protocolMarshaller.marshall(app.getCreateTime(), CREATETIME_BINDING);
              protocolMarshaller.marshall(app.getUpdateTime(), UPDATETIME_BINDING);
              protocolMarshaller.marshall(app.getIamServiceRoleArn(), IAMSERVICEROLEARN_BINDING);
              protocolMarshaller.marshall(app.getEnvironmentVariables(), ENVIRONMENTVARIABLES_BINDING);
              protocolMarshaller.marshall(app.getDefaultDomain(), DEFAULTDOMAIN_BINDING);
              protocolMarshaller.marshall(app.getEnableBranchAutoBuild(), ENABLEBRANCHAUTOBUILD_BINDING);
              protocolMarshaller.marshall(app.getEnableBasicAuth(), ENABLEBASICAUTH_BINDING);
              protocolMarshaller.marshall(app.getBasicAuthCredentials(), BASICAUTHCREDENTIALS_BINDING);
              protocolMarshaller.marshall(app.getCustomRules(), CUSTOMRULES_BINDING);
              protocolMarshaller.marshall(app.getProductionBranch(), PRODUCTIONBRANCH_BINDING);
              protocolMarshaller.marshall(app.getBuildSpec(), BUILDSPEC_BINDING);
          } catch (Exception e) {
              throw new SdkClientException("Unable to marshall request to JSON: " + e.getMessage(), e);
          }
      }
docs: Marshall the given parameter object.