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* Copyright (C) {1999}, International Business Machines Corporation and others. All Rights Reserved.
* Date Name Description
* 11/17/99 aliu Creation.
#ifndef RBT_DATA_H
#define RBT_DATA_H
#include "rbt_set.h"
class UnicodeString;
class UnicodeMatcher;
class Hashtable;
* The rule data for a RuleBasedTransliterators. RBT objects hold
* a const pointer to a TRD object that they do not own. TRD objects
* are essentially the parsed rules in compact, usable form. The
* TRD objects themselves are held for the life of the process in
* a static cache owned by Transliterator.
* This class' API is a little asymmetric. There is a method to
* define a variable, but no way to define a set. This is because the
* sets are defined by the parser in a UVector, and the vector is
* copied into a fixed-size array here. Once this is done, no new
* sets may be defined. In practice, there is no need to do so, since
* generating the data and using it are discrete phases. When there
* is a need to access the set data during the parse phase, another
* data structure handles this. See the parsing code for more
* details.
class TransliterationRuleData {
* Rule table. May be empty.
TransliterationRuleSet ruleSet;
* Map variable name (String) to variable (UnicodeString). A variable name
* corresponds to zero or more characters, stored in a UnicodeString in
* this hash. One or more of these chars may also correspond to a
* UnicodeMatcher, in which case the character in the UnicodeString in this hash is
* a stand-in: it is an index for a secondary lookup in
* data.variables. The stand-in also represents the UnicodeMatcher in
* the stored rules.
Hashtable* variableNames;
* Map category variable (UChar) to set (UnicodeMatcher).
* Variables that correspond to a set of characters are mapped
* from variable name to a stand-in character in data.variableNames.
* The stand-in then serves as a key in this hash to lookup the
* actual UnicodeMatcher object. In addition, the stand-in is
* stored in the rule text to represent the set of characters.
* variables[i] represents character (variablesBase + i).
UnicodeMatcher** variables;
* The character that represents variables[0]. Characters
* variablesBase through variablesBase +
* variablesLength - 1 represent UnicodeMatcher objects.
UChar variablesBase;
* The length of variables.
int32_t variablesLength;
* The character that represents segment 1. Characters segmentBase
* through segmentBase - segmentCount + 1 represent segments 1
* through segmentCount. Segments work down while variables work up.
UChar segmentBase;
int32_t segmentCount;
TransliterationRuleData(UErrorCode& status);
TransliterationRuleData(const TransliterationRuleData&);
* Given a stand-in character, return the UnicodeMatcher that it
* represents, or NULL.
const UnicodeMatcher* lookup(UChar32 standIn) const;
* Return the zero-based index of the segment represented by the given
* character, or -1 if none. Repeat: This is a zero-based return value,
* 0..n-1, even though these are notated "$1".."$n", where n is segmentCount.
int32_t lookupSegmentReference(UChar32 c) const;
* Return the character used to stand for the given segment reference.
* The reference must be in the range 1..segmentCount.
UChar getSegmentStandin(int32_t ref) const {
return (UChar)(segmentBase - ref + 1);