Examples with ColumnSelector io.druid.segment.ColumnSelector used on opensource projects

Example 1 with ColumnSelector

use of io.druid.segment.ColumnSelector in project druid by druid-io.

the class BaseFilterTest method selectColumnValuesMatchingFilterUsingPostFiltering.

private List<String> selectColumnValuesMatchingFilterUsingPostFiltering(final DimFilter filter, final String selectColumn) {
    final Filter theFilter = makeFilter(filter);
    final Filter postFilteringFilter = new Filter() {

        @Override
        public ImmutableBitmap getBitmapIndex(BitmapIndexSelector selector) {
            throw new UnsupportedOperationException();
        }

        @Override
        public ValueMatcher makeMatcher(ColumnSelectorFactory factory) {
            return theFilter.makeMatcher(factory);
        }

        @Override
        public boolean supportsBitmapIndex(BitmapIndexSelector selector) {
            return false;
        }

        @Override
        public boolean supportsSelectivityEstimation(ColumnSelector columnSelector, BitmapIndexSelector indexSelector) {
            return false;
        }

        @Override
        public double estimateSelectivity(BitmapIndexSelector indexSelector) {
            return 1.0;
        }
    };
    final Sequence<Cursor> cursors = makeCursorSequence(postFilteringFilter);
    Sequence<List<String>> seq = Sequences.map(cursors, new Function<Cursor, List<String>>() {

        @Override
        public List<String> apply(Cursor input) {
            final DimensionSelector selector = input.makeDimensionSelector(new DefaultDimensionSpec(selectColumn, selectColumn));
            final List<String> values = Lists.newArrayList();
            while (!input.isDone()) {
                IndexedInts row = selector.getRow();
                Preconditions.checkState(row.size() == 1);
                values.add(selector.lookupName(row.get(0)));
                input.advance();
            }
            return values;
        }
    });
    return Sequences.toList(seq, new ArrayList<List<String>>()).get(0);
}