public void setMd5Digest(String md5Digest) {
        this.md5Digest = md5Digest;
    }
Sets the optional, but recommended, MD5 hash of the content of this part.
If specified, this value will be sent to Amazon S3 to verify the data
integrity when the data reaches Amazon S3.

@param md5Digest
           The optional, but recommended, MD5 hash of the content of this
           part. If specified, this value will be sent to Amazon S3 to
           verify the data integrity when the data reaches Amazon S3.
aws-java-sdk-s3/src/main/java/com/amazonaws/services/s3/model/UploadPartRequest.java