public Builder clearBucketList() {
      if (bucketListBuilder_ == null) {
        if (sourceCase_ == 19) {
          sourceCase_ = 0;
          source_ = null;
          onChanged();
        }
      } else {
        if (sourceCase_ == 19) {
          sourceCase_ = 0;
          source_ = null;
        }
        bucketListBuilder_.clear();
      }
      return this;
    }
<pre>
Specifies a list of buckets and their objects to be transformed.
</pre>

<code>.google.cloud.storagebatchoperations.v1.BucketList bucket_list = 19;</code>
java-storagebatchoperations/proto-google-cloud-storagebatchoperations-v1/src/main/java/com/google/cloud/storagebatchoperations/v1/Job.java