/*
* 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;
namespace Lucene.Net.Search
{
/// Abstract decorator class of a DocIdSetIterator
/// implementation that provides on-demand filter/validation
/// mechanism on an underlying DocIdSetIterator. See
///.
///
public abstract class FilteredDocIdSetIterator:DocIdSetIterator
{
protected internal DocIdSetIterator _innerIter;
private int doc;
/// Constructor.
/// Underlying DocIdSetIterator.
///
protected FilteredDocIdSetIterator(DocIdSetIterator innerIter)
{
if (innerIter == null)
{
throw new System.ArgumentException("null iterator");
}
_innerIter = innerIter;
doc = - 1;
}
/// Validation method to determine whether a docid should be in the result set.
/// docid to be tested
///
/// true if input docid should be in the result set, false otherwise.
///
///
///
public abstract /*protected internal*/ bool Match(int doc);
public override int DocID()
{
return doc;
}
public override int NextDoc()
{
while ((doc = _innerIter.NextDoc()) != NO_MORE_DOCS)
{
if (Match(doc))
{
return doc;
}
}
return doc;
}
public override int Advance(int target)
{
doc = _innerIter.Advance(target);
if (doc != NO_MORE_DOCS)
{
if (Match(doc))
{
return doc;
}
else
{
while ((doc = _innerIter.NextDoc()) != NO_MORE_DOCS)
{
if (Match(doc))
{
return doc;
}
}
return doc;
}
}
return doc;
}
}
}