beagled/Lucene.Net/Search/Filter.cs

   1 /*
   2  * Copyright 2004 The Apache Software Foundation
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 using System;
  18 using IndexReader = Lucene.Net.Index.IndexReader;
  19
  20 namespace Lucene.Net.Search
  21 {
  22
  23         /// <summary>Abstract base class providing a mechanism to restrict searches to a subset
  24         /// of an index.
  25         /// </summary>
  26         [Serializable]
  27         public abstract class Filter
  28         {
  29                 /// <summary>Returns a BitSet with true for documents which should be permitted in
  30                 /// search results, and false for those that should not.
  31                 /// </summary>
  32                 public abstract System.Collections.BitArray Bits(IndexReader reader);
  33         }
  34 }