IPositionIncrementAttribute.cs

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 * 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
 * 
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 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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using System;
using Lucene.Net.Util;

namespace Lucene.Net.Analysis.Tokenattributes
{
    
    /// <summary>The positionIncrement determines the position of this token
    /// relative to the previous Token in a TokenStream, used in phrase
    /// searching.
    /// 
    /// <p/>The default value is one.
    /// 
    /// <p/>Some common uses for this are:<list>
    /// 
    /// <item>Set it to zero to put multiple terms in the same position.  This is
    /// useful if, e.g., a word has multiple stems.  Searches for phrases
    /// including either stem will match.  In this case, all but the first stem's
    /// increment should be set to zero: the increment of the first instance
    /// should be one.  Repeating a token with an increment of zero can also be
    /// used to boost the scores of matches on that token.</item>
    /// 
    /// <item>Set it to values greater than one to inhibit exact phrase matches.
    /// If, for example, one does not want phrases to match across removed stop
    /// words, then one could build a stop word filter that removes stop words and
    /// also sets the increment to the number of stop words removed before each
    /// non-stop word.  Then exact phrase queries will only match when the terms
    /// occur with no intervening stop words.</item>
    /// 
    /// </list>
    /// 
    /// </summary>
    /// <seealso cref="Lucene.Net.Index.TermPositions">
    /// </seealso>
    public interface IPositionIncrementAttribute:IAttribute
    {
        /// <summary>Gets or sets the position increment. The default value is one.
        /// 
        /// </summary>
        /// <value> the distance from the prior term </value>
        int PositionIncrement { set; get; }
    }
}