private boolean isCurrentDataSegmented() {
        return lastResult != null
                && (DataType.SEGMENTED.equals(lastResult.getDataType())
                || DataType.MARKER.equals(lastResult.getDataType()));
    }
Compare the {@link DataRange}s using on the from/to {@link Location};
stroom-core-client/src/main/java/stroom/data/client/presenter/SourcePresenter.java