82 lines
2.6 KiB
C++
82 lines
2.6 KiB
C++
/*
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*****************************************************************************************
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* Copyright (C) 1997-1999, International Business Machines
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* Corporation and others. All Rights Reserved.
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*****************************************************************************************
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*/
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//===============================================================================
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//
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// File colcache.h
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//
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// CollationCache implements a persistent in-memory cache for
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// TableCollationData objects. The goal of CollationCache is to improve
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// the memory footprint of a process which may have multiple threads
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// loading up the same TableCollation object. Performance improvement is
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// strictly a secondary goal.
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//
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// Created by: Alan Liu
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//
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// Modification History:
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//
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// Date Name Description
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// 2/11/97 aliu Creation.
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// 2/12/97 aliu Modified to work with TableCollationData.
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// 8/18/97 helena Added internal API documentation.
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//
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//===============================================================================
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#ifndef COLCACHE_H
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#define COLCACHE_H
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#include "uhash.h"
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#include "unicode/unistr.h"
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class TableCollationData;
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// Tell the VC++ compiler not to warn about DLL interface
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#ifdef _WIN32
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#pragma warning( disable : 4251 )
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#endif
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//-------------------------------------------------------------------------------
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/**
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* CollationCache implements a simple cache for TableCollationData objects.
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* TableCollationData objects may be added to the cache, and looked up in the
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* cache. When the cache is destroyed, all the TableCollationData objects are
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* deleted.
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*/
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class CollationCache
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{
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public:
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/**
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* Default constructor.
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*/
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CollationCache();
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/**
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* Destructor.
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*/
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virtual ~CollationCache();
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/**
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* ::Add and ::Find use a UnicodeString as the key to Collation objects in the
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* cache. If Add is called twice with equivalent keys, but different
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* collation objects, the first collation object will be deleted when the
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* second one is added. In general, this is undesirable; objects in the
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* cache are usually pointed to by various clients in the system. For this
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* reason, clients should call Find to ensure a Collation object does not
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* already exist in the cache for the given key before calling Add.
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* @param key the unique key.
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* @param data the collation data object.
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* @return the found collation data object
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*/
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void Add(const UnicodeString& key, TableCollationData* data);
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TableCollationData* Find(const UnicodeString& key);
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private:
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UHashtable* fHashtable;
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};
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#endif
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//eof
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