public Date getUnmodifiedSinceConstraint() {
        return unmodifiedSinceConstraint;
    }
Gets the optional unmodified constraint that restricts this
request to executing only if the object has <b>not</b> been
modified after the specified date.

@return The optional unmodified constraint that restricts this
        request to executing only if the object has <b>not</b>
        been modified after the specified date.

@see GetObjectRequest#setUnmodifiedSinceConstraint(Date)
@see GetObjectRequest#withUnmodifiedSinceConstraint(Date)
aws-java-sdk-s3/src/main/java/com/amazonaws/services/s3/model/GetObjectRequest.java