00001 /* 00002 * Copyright 2006-2008 The FLWOR Foundation. 00003 * 00004 * Licensed under the Apache License, Version 2.0 (the "License"); 00005 * you may not use this file except in compliance with the License. 00006 * You may obtain a copy of the License at 00007 * 00008 * http://www.apache.org/licenses/LICENSE-2.0 00009 * 00010 * Unless required by applicable law or agreed to in writing, software 00011 * distributed under the License is distributed on an "AS IS" BASIS, 00012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 00013 * See the License for the specific language governing permissions and 00014 * limitations under the License. 00015 */ 00016 00017 #ifndef ZORBA_STEMMER_API_H 00018 #define ZORBA_STEMMER_API_H 00019 00020 #include <zorba/config.h> 00021 00022 #ifndef ZORBA_NO_FULL_TEXT 00023 00024 #include <zorba/internal/unique_ptr.h> 00025 #include <zorba/internal/ztd.h> 00026 #include <zorba/locale.h> 00027 #include <zorba/zorba_string.h> 00028 00029 namespace zorba { 00030 00031 /////////////////////////////////////////////////////////////////////////////// 00032 00033 /** 00034 * A %Stemmer is used to obtain the "stem" (root) word of of some word. For 00035 * example the stem of "flavoring" is "flavor". A %Stemmer is used by the 00036 * XQuery Full Text feature. 00037 */ 00038 class ZORBA_DLL_PUBLIC Stemmer { 00039 public: 00040 typedef std::unique_ptr<Stemmer,internal::ztd::destroy_delete<Stemmer> > ptr; 00041 00042 /** 00043 * Destroys this %Stemmer. 00044 * This function is called by Zorba when the %Stemmer is no longer needed. 00045 * 00046 * If your StemmerProvider dynamically allocates %Stemmer objects, then the 00047 * implementation can simply be (and usually is) <code>delete this</code>. 00048 * 00049 * If your StemmerProvider returns a pointer to a static %Stemmer object, 00050 * then the implementation should do nothing. 00051 */ 00052 virtual void destroy() const = 0; 00053 00054 /** 00055 * Stems the given word. 00056 * 00057 * @param word The word to stem. 00058 * @param lang The language of the word. 00059 * @param result The stemmed word (or the original word if either it and its 00060 * stem are the same word or the stemmer doesn't know how to stem it). 00061 */ 00062 virtual void stem( String const &word, locale::iso639_1::type lang, 00063 String *result ) const = 0; 00064 protected: 00065 virtual ~Stemmer(); 00066 }; 00067 00068 /** 00069 * A %StemmerProvider, given an language, provies a stemmer for it. 00070 */ 00071 class ZORBA_DLL_PUBLIC StemmerProvider { 00072 public: 00073 virtual ~StemmerProvider(); 00074 00075 /** 00076 * Gets a Stemmer for the given language. 00077 * 00078 * @param lang The language to get a Stemmer for. 00079 * @return The relevant Stemmer or \c NULL if no stemmer for the given 00080 * language is available. 00081 */ 00082 virtual Stemmer::ptr getStemmer( locale::iso639_1::type lang ) const = 0; 00083 }; 00084 00085 /////////////////////////////////////////////////////////////////////////////// 00086 00087 } // namespace zorba 00088 #endif /* ZORBA_NO_FULL_TEXT */ 00089 #endif /* ZORBA_STEMMER_API_H */ 00090 /* vim:set et sw=2 ts=2: */