@java.lang.Override
  public com.google.protobuf.ByteString getKeyBytes() {
    java.lang.Object ref = key_;
    if (ref instanceof java.lang.String) {
      com.google.protobuf.ByteString b =
          com.google.protobuf.ByteString.copyFromUtf8((java.lang.String) ref);
      key_ = b;
      return b;
    } else {
      return (com.google.protobuf.ByteString) ref;
    }
  }
<pre>
A unique key for this input attachment. The key must be 1-63
characters in length. The key must begin and end with a letter (regardless
of case) or a number, but can contain dashes or underscores in between.
</pre>

<code>string key = 1;</code>

@return The bytes for key.
java-video-live-stream/proto-google-cloud-live-stream-v1/src/main/java/com/google/cloud/video/livestream/v1/InputAttachment.java