Integer m = (Integer) this.datasetToDomainAxisMap.get(
                        datasetIndex);
                if (m == null) {  // a dataset with no mapping is assigned to
                                  // axis 0
                    if (axisIndex == 0) {
                        result.add(dataset);
                    }
                }
                else {
                    if (m.intValue() == axisIndex) {
                        result.add(dataset);