code: protected ActionResponse asDBFluteApplicationException(ActionRuntime runtime, RuntimeException cause) {
          final ActionResponse response;
          if (cause instanceof EntityAlreadyDeletedException) {
              response = handleEntityAlreadyDeletedException(runtime, (EntityAlreadyDeletedException) cause);
          } else if (cause instanceof EntityAlreadyUpdatedException) {
              response = handleEntityAlreadyUpdatedException(runtime, (EntityAlreadyUpdatedException) cause);
          } else if (cause instanceof EntityAlreadyExistsException) {
              response = handleEntityAlreadyExistsException(runtime, (EntityAlreadyExistsException) cause);
          } else {
              response = ActionResponse.undefined();
          }
          return response;
      }
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