Examples with ColumnSelectorFactory org.apache.druid.segment.ColumnSelectorFactory used on opensource projects

Example 21 with ColumnSelectorFactory

use of org.apache.druid.segment.ColumnSelectorFactory 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 <T> T getBitmapResult(BitmapIndexSelector selector, BitmapResultFactory<T> bitmapResultFactory) {
            throw new UnsupportedOperationException();
        }

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

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

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

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

        @Override
        public Set<String> getRequiredColumns() {
            return Collections.emptySet();
        }

        @Override
        public double estimateSelectivity(BitmapIndexSelector indexSelector) {
            return 1.0;
        }
    };
    final Sequence<Cursor> cursors = makeCursorSequence(postFilteringFilter);
    Sequence<List<String>> seq = Sequences.map(cursors, cursor -> {
        final DimensionSelector selector = cursor.getColumnSelectorFactory().makeDimensionSelector(new DefaultDimensionSpec(selectColumn, selectColumn));
        final List<String> values = new ArrayList<>();
        while (!cursor.isDone()) {
            IndexedInts row = selector.getRow();
            Preconditions.checkState(row.size() == 1);
            values.add(selector.lookupName(row.get(0)));
            cursor.advance();
        }
        return values;
    });
    return seq.toList().get(0);
}