public Builder mergePutMetadata(com.google.cloud.storagebatchoperations.v1.PutMetadata value) {
      if (putMetadataBuilder_ == null) {
        if (transformationCase_ == 8
            && transformation_
                != com.google.cloud.storagebatchoperations.v1.PutMetadata.getDefaultInstance()) {
          transformation_ =
              com.google.cloud.storagebatchoperations.v1.PutMetadata.newBuilder(
                      (com.google.cloud.storagebatchoperations.v1.PutMetadata) transformation_)
                  .mergeFrom(value)
                  .buildPartial();
        } else {
          transformation_ = value;
        }
        onChanged();
      } else {
        if (transformationCase_ == 8) {
          putMetadataBuilder_.mergeFrom(value);
        } else {
          putMetadataBuilder_.setMessage(value);
        }
      }
      transformationCase_ = 8;
      return this;
    }
<pre>
Updates object metadata. Allows updating fixed-key and custom metadata
and fixed-key metadata i.e. Cache-Control, Content-Disposition,
Content-Encoding, Content-Language, Content-Type, Custom-Time.
</pre>

<code>.google.cloud.storagebatchoperations.v1.PutMetadata put_metadata = 8;</code>
java-storagebatchoperations/proto-google-cloud-storagebatchoperations-v1/src/main/java/com/google/cloud/storagebatchoperations/v1/Job.java