content: /**
   * 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.tier;
  
  import java.io.IOException;
  import java.util.List;
  
  import org.apache.lucene.index.IndexReader;
  import org.apache.lucene.index.Term;
  import org.apache.lucene.index.TermDocs;
  import org.apache.lucene.search.Filter;
  import org.apache.lucene.search.DocIdSet;
  import org.apache.lucene.util.NumericUtils;
  import org.apache.lucene.util.FixedBitSet;
  
  /**
   * <p><font color="red"><b>NOTE:</b> This API is still in
   * flux and might change in incompatible ways in the next
   * release.</font>
   */
  public class CartesianShapeFilter extends Filter {
   
    private final Shape shape;
    private final String fieldName;
    
    CartesianShapeFilter(final Shape shape, final String fieldName){
      this.shape = shape;
      this.fieldName = fieldName;
    }
    
    @Override
    public DocIdSet getDocIdSet(final IndexReader reader) throws IOException {
      final FixedBitSet bits = new FixedBitSet(reader.maxDoc());
      final TermDocs termDocs = reader.termDocs();
      final List<Double> area = shape.getArea();
      int sz = area.size();
      
      final Term term = new Term(fieldName);
      // iterate through each boxid
      for (int i =0; i< sz; i++) {
        double boxId = area.get(i).doubleValue();
        termDocs.seek(term.createTerm(NumericUtils.doubleToPrefixCoded(boxId)));
        // iterate through all documents
        // which have this boxId
        while (termDocs.next()) {
          bits.set(termDocs.doc());
        }
      }
      return bits;
    }
  }
  