| using Lucene.Net.Analysis.TokenAttributes; |
| using System; |
| using System.Collections.Generic; |
| using System.IO; |
| using System.Text; |
| |
| namespace Lucene.Net.Analysis.Path |
| { |
| /* |
| * 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. |
| */ |
| |
| /// <summary> |
| /// Tokenizer for domain-like hierarchies. |
| /// <para> |
| /// Take something like: |
| /// |
| /// <code> |
| /// www.site.co.uk |
| /// </code> |
| /// |
| /// and make: |
| /// |
| /// <code> |
| /// www.site.co.uk |
| /// site.co.uk |
| /// co.uk |
| /// uk |
| /// </code> |
| /// |
| /// </para> |
| /// </summary> |
| public class ReversePathHierarchyTokenizer : Tokenizer |
| { |
| public ReversePathHierarchyTokenizer(TextReader input) |
| : this(input, DEFAULT_BUFFER_SIZE, DEFAULT_DELIMITER, DEFAULT_DELIMITER, DEFAULT_SKIP) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(TextReader input, int skip) |
| : this(input, DEFAULT_BUFFER_SIZE, DEFAULT_DELIMITER, DEFAULT_DELIMITER, skip) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(TextReader input, int bufferSize, char delimiter) |
| : this(input, bufferSize, delimiter, delimiter, DEFAULT_SKIP) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(TextReader input, char delimiter, char replacement) |
| : this(input, DEFAULT_BUFFER_SIZE, delimiter, replacement, DEFAULT_SKIP) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(TextReader input, int bufferSize, char delimiter, char replacement) |
| : this(input, bufferSize, delimiter, replacement, DEFAULT_SKIP) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(TextReader input, char delimiter, int skip) |
| : this(input, DEFAULT_BUFFER_SIZE, delimiter, delimiter, skip) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(TextReader input, char delimiter, char replacement, int skip) |
| : this(input, DEFAULT_BUFFER_SIZE, delimiter, replacement, skip) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(AttributeFactory factory, TextReader input, char delimiter, char replacement, int skip) |
| : this(factory, input, DEFAULT_BUFFER_SIZE, delimiter, replacement, skip) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(TextReader input, int bufferSize, char delimiter, char replacement, int skip) |
| : this(AttributeFactory.DEFAULT_ATTRIBUTE_FACTORY, input, bufferSize, delimiter, replacement, skip) |
| { |
| } |
| |
| public ReversePathHierarchyTokenizer(AttributeFactory factory, TextReader input, int bufferSize, char delimiter, char replacement, int skip) |
| : base(factory, input) |
| { |
| if (bufferSize < 0) |
| { |
| throw new ArgumentException("bufferSize cannot be negative"); |
| } |
| if (skip < 0) |
| { |
| throw new ArgumentException("skip cannot be negative"); |
| } |
| termAtt = AddAttribute<ICharTermAttribute>(); |
| offsetAtt = AddAttribute<IOffsetAttribute>(); |
| posAtt = AddAttribute<IPositionIncrementAttribute>(); |
| |
| termAtt.ResizeBuffer(bufferSize); |
| this.delimiter = delimiter; |
| this.replacement = replacement; |
| this.skip = skip; |
| resultToken = new StringBuilder(bufferSize); |
| resultTokenBuffer = new char[bufferSize]; |
| delimiterPositions = new List<int>(bufferSize / 10); |
| } |
| |
| private const int DEFAULT_BUFFER_SIZE = 1024; |
| public const char DEFAULT_DELIMITER = '/'; |
| public const int DEFAULT_SKIP = 0; |
| |
| private readonly char delimiter; |
| private readonly char replacement; |
| private readonly int skip; |
| |
| private readonly ICharTermAttribute termAtt; |
| private readonly IOffsetAttribute offsetAtt; |
| private readonly IPositionIncrementAttribute posAtt; |
| |
| private int endPosition = 0; |
| private int finalOffset = 0; |
| private int skipped = 0; |
| private readonly StringBuilder resultToken; |
| |
| private readonly IList<int> delimiterPositions; |
| private int delimitersCount = -1; |
| private char[] resultTokenBuffer; |
| |
| public override sealed bool IncrementToken() |
| { |
| ClearAttributes(); |
| if (delimitersCount == -1) |
| { |
| int length = 0; |
| delimiterPositions.Add(0); |
| while (true) |
| { |
| int c = m_input.Read(); |
| if (c < 0) |
| { |
| break; |
| } |
| length++; |
| if (c == delimiter) |
| { |
| delimiterPositions.Add(length); |
| resultToken.Append(replacement); |
| } |
| else |
| { |
| resultToken.Append((char)c); |
| } |
| } |
| delimitersCount = delimiterPositions.Count; |
| if (delimiterPositions[delimitersCount - 1] < length) |
| { |
| delimiterPositions.Add(length); |
| delimitersCount++; |
| } |
| if (resultTokenBuffer.Length < resultToken.Length) |
| { |
| resultTokenBuffer = new char[resultToken.Length]; |
| } |
| resultToken.CopyTo(0, resultTokenBuffer, 0, resultToken.Length); |
| resultToken.Length = 0; |
| int idx = delimitersCount - 1 - skip; |
| if (idx >= 0) |
| { |
| // otherwise its ok, because we will skip and return false |
| endPosition = delimiterPositions[idx]; |
| } |
| finalOffset = CorrectOffset(length); |
| posAtt.PositionIncrement = 1; |
| } |
| else |
| { |
| posAtt.PositionIncrement = 0; |
| } |
| |
| while (skipped < delimitersCount - skip - 1) |
| { |
| var start = delimiterPositions[skipped]; |
| termAtt.CopyBuffer(resultTokenBuffer, start, endPosition - start); |
| offsetAtt.SetOffset(CorrectOffset(start), CorrectOffset(endPosition)); |
| skipped++; |
| return true; |
| } |
| |
| return false; |
| } |
| |
| public override sealed void End() |
| { |
| base.End(); |
| // set final offset |
| offsetAtt.SetOffset(finalOffset, finalOffset); |
| } |
| |
| public override void Reset() |
| { |
| base.Reset(); |
| resultToken.Length = 0; |
| finalOffset = 0; |
| endPosition = 0; |
| skipped = 0; |
| delimitersCount = -1; |
| delimiterPositions.Clear(); |
| } |
| } |
| } |