@java.lang.Override
    public java.lang.String getManifestKey() {
      java.lang.Object ref = manifestKey_;
      if (ref instanceof java.lang.String) {
        return (java.lang.String) ref;
      } else {
        com.google.protobuf.ByteString bs = (com.google.protobuf.ByteString) ref;
        java.lang.String s = bs.toStringUtf8();
        manifestKey_ = s;
        return s;
      }
    }
<pre>
Required. A unique key that identifies a manifest config in the parent
channel. This key is the same as `channel.manifests.key` for the selected
manifest.
</pre>

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

@return The manifestKey.
java-video-live-stream/proto-google-cloud-live-stream-v1/src/main/java/com/google/cloud/video/livestream/v1/DvrSession.java