io.druid.segment.filter.ExtractionFilter.java Source code

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Here is the source code for io.druid.segment.filter.ExtractionFilter.java

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/*
 * Druid - a distributed column store.
 * Copyright 2012 - 2015 Metamarkets Group Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.druid.segment.filter;

import com.google.common.base.Predicate;
import com.google.common.base.Strings;
import com.google.common.collect.Lists;
import com.metamx.collections.bitmap.ImmutableBitmap;
import io.druid.query.extraction.ExtractionFn;
import io.druid.query.filter.BitmapIndexSelector;
import io.druid.query.filter.Filter;
import io.druid.query.filter.ValueMatcher;
import io.druid.query.filter.ValueMatcherFactory;
import io.druid.segment.ColumnSelectorFactory;
import io.druid.segment.DimensionSelector;
import io.druid.segment.data.Indexed;
import io.druid.segment.data.IndexedInts;

import java.util.BitSet;
import java.util.Iterator;
import java.util.List;

/**
 */
public class ExtractionFilter implements Filter {
    private final String dimension;
    private final String value;
    private final ExtractionFn fn;

    public ExtractionFilter(String dimension, String value, ExtractionFn fn) {
        this.dimension = dimension;
        this.value = Strings.nullToEmpty(value);
        this.fn = fn;
    }

    private List<Filter> makeFilters(BitmapIndexSelector selector) {
        Indexed<String> allDimVals = selector.getDimensionValues(dimension);
        final List<Filter> filters = Lists.newArrayList();
        if (allDimVals == null) {
            allDimVals = new Indexed<String>() {
                @Override
                public Iterator<String> iterator() {
                    return null;
                }

                @Override
                public Class<? extends String> getClazz() {
                    return null;
                }

                @Override
                public int size() {
                    return 1;
                }

                @Override
                public String get(int index) {
                    return null;
                }

                @Override
                public int indexOf(String value) {
                    return 0;
                }
            };
        }

        for (int i = 0; i < allDimVals.size(); i++) {
            String dimVal = allDimVals.get(i);
            if (value.equals(Strings.nullToEmpty(fn.apply(dimVal)))) {
                filters.add(new SelectorFilter(dimension, dimVal));
            }
        }

        return filters;
    }

    @Override
    public ImmutableBitmap getBitmapIndex(BitmapIndexSelector selector) {
        final List<Filter> filters = makeFilters(selector);
        if (filters.isEmpty()) {
            return selector.getBitmapFactory().makeEmptyImmutableBitmap();
        }
        return new OrFilter(makeFilters(selector)).getBitmapIndex(selector);
    }

    @Override
    public ValueMatcher makeMatcher(ValueMatcherFactory factory) {
        return factory.makeValueMatcher(dimension, new Predicate<String>() {
            @Override
            public boolean apply(String input) {
                // Assuming that a null/absent/empty dimension are equivalent from the druid perspective
                return value.equals(Strings.nullToEmpty(fn.apply(Strings.emptyToNull(input))));
            }
        });
    }

    @Override
    public ValueMatcher makeMatcher(ColumnSelectorFactory columnSelectorFactory) {
        final DimensionSelector dimensionSelector = columnSelectorFactory.makeDimensionSelector(dimension, null);
        if (dimensionSelector == null) {
            return new BooleanValueMatcher(value.equals(Strings.nullToEmpty(fn.apply(null))));
        } else {
            final BitSet bitSetOfIds = new BitSet(dimensionSelector.getValueCardinality());
            for (int i = 0; i < dimensionSelector.getValueCardinality(); i++) {
                if (value.equals(Strings.nullToEmpty(fn.apply(dimensionSelector.lookupName(i))))) {
                    bitSetOfIds.set(i);
                }
            }
            return new ValueMatcher() {
                @Override
                public boolean matches() {
                    final IndexedInts row = dimensionSelector.getRow();
                    final int size = row.size();
                    for (int i = 0; i < size; ++i) {
                        if (bitSetOfIds.get(row.get(i))) {
                            return true;
                        }
                    }
                    return false;
                }
            };
        }
    }

}