public String getVersionId() {
        return s3ObjectIdBuilder.getVersionId();
    }
<p>
Gets the optional version ID specifying which version of the object to
download. If not specified, the most recent version will be downloaded.
</p>
<p>
Objects created before versioning was enabled or when versioning is
suspended are given the default <code>null</code> version ID (see
{@link Constants#NULL_VERSION_ID}). Note that the
<code>null</code> version ID is a valid version ID and is not the
same as not having a version ID.
</p>
<p>
For more information about enabling versioning for a bucket, see
{@link AmazonS3#setBucketVersioningConfiguration(SetBucketVersioningConfigurationRequest)}.
</p>

@return The optional version ID specifying which version of the object to
        download. If not specified, the most recent version will be
        downloaded.

@see GetObjectRequest#setVersionId(String)
@see GetObjectRequest#withVersionId(String)
aws-java-sdk-s3/src/main/java/com/amazonaws/services/s3/model/GetObjectRequest.java