| using Lucene.Net.Analysis.TokenAttributes; |
| using Lucene.Net.Analysis.Util; |
| using Lucene.Net.Util; |
| |
| namespace Lucene.Net.Analysis.Core |
| { |
| /* |
| * 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> |
| /// Normalizes token text to UPPER CASE. |
| /// <para> |
| /// You must specify the required <see cref="LuceneVersion"/> |
| /// compatibility when creating <see cref="UpperCaseFilter"/> |
| /// </para> |
| /// <para><b>NOTE:</b> In Unicode, this transformation may lose information when the |
| /// upper case character represents more than one lower case character. Use this filter |
| /// when you Require uppercase tokens. Use the <see cref="LowerCaseFilter"/> for |
| /// general search matching |
| /// </para> |
| /// </summary> |
| public sealed class UpperCaseFilter : TokenFilter |
| { |
| private readonly CharacterUtils charUtils; |
| private readonly ICharTermAttribute termAtt; |
| |
| /// <summary> |
| /// Create a new <see cref="UpperCaseFilter"/>, that normalizes token text to upper case. |
| /// </summary> |
| /// <param name="matchVersion"> See <see cref="LuceneVersion"/> </param> |
| /// <param name="in"> <see cref="TokenStream"/> to filter </param> |
| public UpperCaseFilter(LuceneVersion matchVersion, TokenStream @in) |
| : base(@in) |
| { |
| termAtt = AddAttribute<ICharTermAttribute>(); |
| charUtils = CharacterUtils.GetInstance(matchVersion); |
| } |
| |
| public override sealed bool IncrementToken() |
| { |
| if (m_input.IncrementToken()) |
| { |
| charUtils.ToUpper(termAtt.Buffer, 0, termAtt.Length); |
| return true; |
| } |
| else |
| { |
| return false; |
| } |
| } |
| } |
| } |