/*
* 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.
*/
using System;
using System.Collections.Generic;
using IndexReader = Lucene.Net.Index.IndexReader;
using OpenBitSet = Lucene.Net.Util.OpenBitSet;
using SpanQuery = Lucene.Net.Search.Spans.SpanQuery;
namespace Lucene.Net.Search
{
/// Constrains search results to only match those which also match a provided
/// query. Also provides position information about where each document matches
/// at the cost of extra space compared with the QueryWrapperFilter.
/// There is an added cost to this above what is stored in a . Namely,
/// the position information for each matching document is stored.
///
/// This filter does not cache. See the for a wrapper that
/// caches.
///
///
///
/// $Id:$
///
[Serializable]
public class SpanQueryFilter:SpanFilter
{
protected internal SpanQuery query;
protected internal SpanQueryFilter()
{
}
/// Constructs a filter which only matches documents matching
/// query.
///
/// The to use as the basis for the Filter.
///
public SpanQueryFilter(SpanQuery query)
{
this.query = query;
}
public override DocIdSet GetDocIdSet(IndexReader reader)
{
SpanFilterResult result = BitSpans(reader);
return result.DocIdSet;
}
public override SpanFilterResult BitSpans(IndexReader reader)
{
OpenBitSet bits = new OpenBitSet(reader.MaxDoc);
Lucene.Net.Search.Spans.Spans spans = query.GetSpans(reader);
IList tmp = new List(20);
int currentDoc = - 1;
SpanFilterResult.PositionInfo currentInfo = null;
while (spans.Next())
{
int doc = spans.Doc();
bits.Set(doc);
if (currentDoc != doc)
{
currentInfo = new SpanFilterResult.PositionInfo(doc);
tmp.Add(currentInfo);
currentDoc = doc;
}
currentInfo.AddPosition(spans.Start(), spans.End());
}
return new SpanFilterResult(bits, tmp);
}
public virtual SpanQuery Query
{
get { return query; }
}
public override System.String ToString()
{
return "SpanQueryFilter(" + query + ")";
}
public override bool Equals(System.Object o)
{
return o is SpanQueryFilter && this.query.Equals(((SpanQueryFilter) o).query);
}
public override int GetHashCode()
{
return query.GetHashCode() ^ unchecked((int) 0x923F64B9);
}
}
}