public com.google.protobuf.ByteString getAppIdBytes() {
      java.lang.Object ref = appId_;
      if (ref instanceof String) {
        com.google.protobuf.ByteString b =
            com.google.protobuf.ByteString.copyFromUtf8((java.lang.String) ref);
        appId_ = b;
        return b;
      } else {
        return (com.google.protobuf.ByteString) ref;
      }
    }
<pre>
Required. The App ID is supplied as an HTTP parameter. Unlike internal
usage of App ID, it does not include a region prefix. Rather, the App ID
represents the Project ID against which to make the request.
</pre>

<code>string app_id = 1 [(.google.api.field_behavior) = REQUIRED];</code>

@return The bytes for appId.
java-tasks/proto-google-cloud-tasks-v2beta2/src/main/java/com/google/cloud/tasks/v2beta2/UploadQueueYamlRequest.java