@java.lang.Override
      public boolean hasS3Metadata() {
        return dataProviderCase_ == 4;
      }
<pre>
A S3 compatible metadata.
</pre>

<code>.google.storagetransfer.v1.S3CompatibleMetadata s3_metadata = 4;</code>

@return Whether the s3Metadata field is set.
java-storage-transfer/proto-google-cloud-storage-transfer-v1/src/main/java/com/google/storagetransfer/v1/proto/TransferTypes.java