| /*------------------------------------------------------------------------------ | |
| * Copyright (C) 2003-2006 Ben van Klinken and the CLucene Team | |
| * | |
| * Distributable under the terms of either the Apache License (Version 2.0) or | |
| * the GNU Lesser General Public License, as specified in the COPYING file. | |
| ------------------------------------------------------------------------------*/ | |
| #ifndef _lucene_search_Filter_ | |
| #define _lucene_search_Filter_ | |
| #if defined(_LUCENE_PRAGMA_ONCE) | |
| # pragma once | |
| #endif | |
| #include "CLucene/index/IndexReader.h" | |
| #include "CLucene/util/BitSet.h" | |
| CL_NS_DEF(search) | |
| // Abstract base class providing a mechanism to restrict searches to a subset | |
| // of an index. | |
| class Filter: LUCENE_BASE { | |
| public: | |
| virtual ~Filter(){ | |
| } | |
| virtual Filter* clone() const = 0; | |
| /** | |
| * Returns a BitSet with true for documents which should be permitted in | |
| * search results, and false for those that should not. | |
| * MEMORY: read shouldDeleteBitSet | |
| */ | |
| virtual CL_NS(util)::BitSet* bits(CL_NS(index)::IndexReader* reader)=0; | |
| /** | |
| * Because of the problem of cached bitsets with the CachingWrapperFilter, | |
| * CLucene has no way of knowing whether to delete the bitset returned from bits(). | |
| * To properly clean memory from bits(), pass the bitset to this function. The | |
| * Filter should be deleted if this function returns true. | |
| */ | |
| virtual bool shouldDeleteBitSet(const CL_NS(util)::BitSet* bs) const{ return true; } | |
| //Creates a user-readable version of this query and returns it as as string | |
| virtual TCHAR* toString()=0; | |
| }; | |
| CL_NS_END | |
| #endif |