public void setMarker(String marker) {
        this.marker = marker;
    }
Sets the optional marker parameter indicating where in the bucket to begin
listing. The list will only include keys that occur lexicographically
after the marker.

@param marker
           The optional marker parameter indicating where in the bucket to begin
           listing. The list will only include keys that occur
           lexicographically after the marker.

@see ListObjectsRequest#getMarker()
@see ListObjectsRequest#withMarker(String)
aws-java-sdk-s3/src/main/java/com/amazonaws/services/s3/model/ListObjectsRequest.java