/*
* Copyright 2004 The Apache Software Foundation
*
* Licensed 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.Analysis{
/// <summary> Removes words that are too long and too short from the stream.
///
/// </summary>
/// <author> David Spencer
/// </author>
/// <version> $Id: LengthFilter.java 347992 2005-11-21 21:41:43Z dnaber $
/// </version>
public sealed class LengthFilter : TokenFilter
{
internal int min;
internal int max;
/// <summary> Build a filter that removes words that are too long or too
/// short from the text.
/// </summary>
public LengthFilter(TokenStream in_Renamed, int min, int max) : base(in_Renamed)
{
this.min = min;
this.max = max;
}
/// <summary> Returns the next input Token whose termText() is the right len</summary>
public override Token Next()
{
// return the first non-stop word found
for (Token token = input.Next(); token != null; token = input.Next())
{
int len = token.TermText().Length;
if (len >= min && len <= max)
{
return token;
}
// note: else we ignore it but should we index each part of it?
}
// reached EOS -- return null
return null;
}
}
}
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