@Override
    public String getVersionId() {
        return versionId;
    }
Gets the optional version ID of the newly uploaded object. This field will
be set only if object versioning is enabled for the bucket the
object was uploaded to.

@return The optional version ID of the newly uploaded object.

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