org.apache.lucene.spatial.geopoint.search.GeoPointNumericTermsEnum Maven / Gradle / Ivy

Go to download
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.lucene.spatial.geopoint.search;

import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.spatial.geopoint.document.GeoPointField;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.BytesRefBuilder;
import org.apache.lucene.util.LegacyNumericUtils;

import static org.apache.lucene.spatial.geopoint.document.GeoPointField.BITS;

/**
 * Decomposes a given {@link GeoPointMultiTermQuery} into a set of terms that represent the query criteria using
 * {@link org.apache.lucene.spatial.geopoint.document.GeoPointField.TermEncoding#NUMERIC} method defined by
 * {@link org.apache.lucene.analysis.LegacyNumericTokenStream}. The terms are then enumerated by the
 * {@link GeoPointTermQueryConstantScoreWrapper} and all docs whose GeoPoint fields match the prefix terms or
 * pass the {@link GeoPointMultiTermQuery.CellComparator#postFilter} criteria are returned in the resulting DocIdSet.
 *
 *  @lucene.experimental
 */
@Deprecated
final class GeoPointNumericTermsEnum extends GeoPointTermsEnum {
  private final List rangeBounds = new LinkedList<>();
  private final BytesRefBuilder nextSubRangeBRB = new BytesRefBuilder();

  // detail level should be a factor of PRECISION_STEP limiting the depth of recursion (and number of ranges)
  private final short DETAIL_LEVEL;

  GeoPointNumericTermsEnum(final TermsEnum tenum, final GeoPointMultiTermQuery query) {
    super(tenum, query);
    DETAIL_LEVEL = (short)(((BITS<<1)-this.maxShift)/2);
    computeRange(0L, (short) (((BITS) << 1) - 1));
    assert rangeBounds.isEmpty() == false;
    Collections.sort(rangeBounds);
  }

  /**
   * entry point for recursively computing ranges
   */
  private final void computeRange(long term, final short shift) {
    final long split = term | (0x1L<>>1);

    // if cell is within and a factor of the precision step, or it crosses the edge of the shape add the range
    final boolean within = res % GeoPointField.PRECISION_STEP == 0 && relationImpl.cellWithin(minLat, maxLat, minLon, maxLon);
    if (within || (level == DETAIL_LEVEL && relationImpl.cellIntersectsShape(minLat, maxLat, minLon, maxLon))) {
      final short nextRes = (short)(res-1);
      if (nextRes % GeoPointField.PRECISION_STEP == 0) {
        rangeBounds.add(new Range(start, nextRes, !within));
        rangeBounds.add(new Range(start|(1L< 0) {
        nextRange();
        if (!rangeBounds.isEmpty()) {
          continue;
        }
      }
      // never seek backwards, so use current term if lower bound is smaller
      return (term != null && term.compareTo(currentCell) > 0) ? term : currentCell;
    }

    // no more sub-range enums available
    assert rangeBounds.isEmpty();
    return null;
  }

  /**
   * The two-phase query approach. {@link #nextSeekTerm} is called to obtain the next term that matches a numeric
   * range of the bounding box. Those terms that pass the initial range filter are then compared against the
   * decoded min/max latitude and longitude values of the bounding box only if the range is not a "boundary" range
   * (e.g., a range that straddles the boundary of the bbox).
   * @param term term for candidate document
   * @return match status
   */
  @Override
  protected AcceptStatus accept(BytesRef term) {
    // validate value is in range
    while (currentCell == null || term.compareTo(currentCell) > 0) {
      if (hasNext() == false) {
        return AcceptStatus.END;
      }
      // peek next sub-range, only seek if the current term is smaller than next lower bound
      if (term.compareTo(peek()) < 0) {
        return AcceptStatus.NO_AND_SEEK;
      }
      nextRange();
    }

    return AcceptStatus.YES;
  }

  @Override
  protected final boolean hasNext() {
    return rangeBounds.isEmpty() == false;
  }
}