content: package org.apache.lucene.util;
  
  /**
   * 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.
   */
  
  import java.io.IOException;
  import org.apache.lucene.search.DocIdSetIterator;
   
  public class OpenBitSetDISI extends OpenBitSet {
  
    /** Construct an OpenBitSetDISI with its bits set
     * from the doc ids of the given DocIdSetIterator.
     * Also give a maximum size one larger than the largest doc id for which a
     * bit may ever be set on this OpenBitSetDISI.
     */
    public OpenBitSetDISI(DocIdSetIterator disi, int maxSize) throws IOException {
      super(maxSize);
      inPlaceOr(disi);
    }
  
    /** Construct an OpenBitSetDISI with no bits set, and a given maximum size
     * one larger than the largest doc id for which a bit may ever be set
     * on this OpenBitSetDISI.
     */
    public OpenBitSetDISI(int maxSize) {
      super(maxSize);
    }
  
    /**
     * Perform an inplace OR with the doc ids from a given DocIdSetIterator,
     * setting the bit for each such doc id.
     * These doc ids should be smaller than the maximum size passed to the
     * constructor.
     */   
    public void inPlaceOr(DocIdSetIterator disi) throws IOException {
      int doc;
      long size = size();
      while ((doc = disi.nextDoc()) < size) {
        fastSet(doc);
      }
    }
  
    /**
     * Perform an inplace AND with the doc ids from a given DocIdSetIterator,
     * leaving only the bits set for which the doc ids are in common.
     * These doc ids should be smaller than the maximum size passed to the
     * constructor.
     */   
    public void inPlaceAnd(DocIdSetIterator disi) throws IOException {
      int bitSetDoc = nextSetBit(0);
      int disiDoc;
      while (bitSetDoc != -1 && (disiDoc = disi.advance(bitSetDoc)) != DocIdSetIterator.NO_MORE_DOCS) {
        clear(bitSetDoc, disiDoc);
        bitSetDoc = nextSetBit(disiDoc + 1);
      }
      if (bitSetDoc != -1) {
        clear(bitSetDoc, size());
      }
    }
  
    /**
     * Perform an inplace NOT with the doc ids from a given DocIdSetIterator,
     * clearing all the bits for each such doc id.
     * These doc ids should be smaller than the maximum size passed to the
     * constructor.
     */   
    public void inPlaceNot(DocIdSetIterator disi) throws IOException {
      int doc;
      long size = size();
      while ((doc = disi.nextDoc()) < size) {
        fastClear(doc);
      }
    }
  
    /**
     * Perform an inplace XOR with the doc ids from a given DocIdSetIterator,
     * flipping all the bits for each such doc id.
     * These doc ids should be smaller than the maximum size passed to the
     * constructor.
     */   
    public void inPlaceXor(DocIdSetIterator disi) throws IOException {
      int doc;
      long size = size();
      while ((doc = disi.nextDoc()) < size) {
        fastFlip(doc);
      }
    }
  }
  