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// © 2016 and later: Unicode, Inc. and others.
/*
******************************************************************************
* Copyright (C) 2015, International Business Machines Corporation and
* others. All Rights Reserved.
******************************************************************************
*
* File pluralmap.h - PluralMap class that maps plural categories to values.
******************************************************************************
*/
#ifndef __PLURAL_MAP_H__
#define __PLURAL_MAP_H__
#include "unicode/uobject.h"
#include "cmemory.h"
U_NAMESPACE_BEGIN
class UnicodeString;
class U_COMMON_API PluralMapBase : public UMemory {
public:
/**
* The names of all the plural categories. NONE is not an actual plural
* category, but rather represents the absence of a plural category.
*/
enum Category {
NONE = -1,
OTHER,
ZERO,
ONE,
TWO,
FEW,
MANY,
CATEGORY_COUNT
};
/**
* Converts a category name such as "zero", "one", "two", "few", "many"
* or "other" to a category enum. Returns NONE for an unrecognized
* category name.
*/
static Category toCategory(const char *categoryName);
/**
* Converts a category name such as "zero", "one", "two", "few", "many"
* or "other" to a category enum. Returns NONE for unrecognized
* category name.
*/
static Category toCategory(const UnicodeString &categoryName);
/**
* Converts a category to a name.
* Passing NONE or CATEGORY_COUNT for category returns nullptr.
*/
static const char *getCategoryName(Category category);
};
/**
* A Map of plural categories to values. It maintains ownership of the
* values.
*
* Type T is the value type. T must provide the following:
* 1) Default constructor
* 2) Copy constructor
* 3) Assignment operator
* 4) Must extend UMemory
*/
template<typename T>
class PluralMap : public PluralMapBase {
public:
/**
* Other category is maps to a copy of the default value.
*/
PluralMap() : fOtherVariant() {
initializeNew();
}
/**
* Other category is mapped to otherVariant.
*/
PluralMap(const T &otherVariant) : fOtherVariant(otherVariant) {
initializeNew();
}
PluralMap(const PluralMap<T> &other) : fOtherVariant(other.fOtherVariant) {
fVariants[0] = &fOtherVariant;
for (int32_t i = 1; i < UPRV_LENGTHOF(fVariants); ++i) {
fVariants[i] = other.fVariants[i] ?
new T(*other.fVariants[i]) : nullptr;
}
}
PluralMap<T> &operator=(const PluralMap<T> &other) {
if (this == &other) {
return *this;
}
for (int32_t i = 0; i < UPRV_LENGTHOF(fVariants); ++i) {
if (fVariants[i] != nullptr && other.fVariants[i] != nullptr) {
*fVariants[i] = *other.fVariants[i];
} else if (fVariants[i] != nullptr) {
delete fVariants[i];
fVariants[i] = nullptr;
} else if (other.fVariants[i] != nullptr) {
fVariants[i] = new T(*other.fVariants[i]);
} else {
// do nothing
}
}
return *this;
}
~PluralMap() {
for (int32_t i = 1; i < UPRV_LENGTHOF(fVariants); ++i) {
delete fVariants[i];
}
}
/**
* Removes all mappings and makes 'other' point to the default value.
*/
void clear() {
*fVariants[0] = T();
for (int32_t i = 1; i < UPRV_LENGTHOF(fVariants); ++i) {
delete fVariants[i];
fVariants[i] = nullptr;
}
}
/**
* Iterates through the mappings in this instance, set index to NONE
* prior to using. Call next repeatedly to get the values until it
* returns nullptr. Each time next returns, caller may pass index
* to getCategoryName() to get the name of the plural category.
* When this function returns nullptr, index is CATEGORY_COUNT
*/
const T *next(Category &index) const {
int32_t idx = index;
++idx;
for (; idx < UPRV_LENGTHOF(fVariants); ++idx) {
if (fVariants[idx] != nullptr) {
index = static_cast<Category>(idx);
return fVariants[idx];
}
}
index = static_cast<Category>(idx);
return nullptr;
}
/**
* non const version of next.
*/
T *nextMutable(Category &index) {
const T *result = next(index);
return const_cast<T *>(result);
}
/**
* Returns the 'other' variant.
* Same as calling get(OTHER).
*/
const T &getOther() const {
return get(OTHER);
}
/**
* Returns the value associated with a category.
* If no value found, or v is NONE or CATEGORY_COUNT, falls
* back to returning the value for the 'other' category.
*/
const T &get(Category v) const {
int32_t index = v;
if (index < 0 || index >= UPRV_LENGTHOF(fVariants) || fVariants[index] == nullptr) {
return *fVariants[0];
}
return *fVariants[index];
}
/**
* Convenience routine to get the value by category name. Otherwise
* works just like get(Category).
*/
const T &get(const char *category) const {
return get(toCategory(category));
}
/**
* Convenience routine to get the value by category name as a
* UnicodeString. Otherwise works just like get(category).
*/
const T &get(const UnicodeString &category) const {
return get(toCategory(category));
}
/**
* Returns a pointer to the value associated with a category
* that caller can safely modify. If the value was defaulting to the 'other'
* variant because no explicit value was stored, this method creates a
* new value using the default constructor at the returned pointer.
*
* @param category the category with the value to change.
* @param status error returned here if index is NONE or CATEGORY_COUNT
* or memory could not be allocated, or any other error happens.
*/
T *getMutable(
Category category,
UErrorCode &status) {
return getMutable(category, nullptr, status);
}
/**
* Convenience routine to get a mutable pointer to a value by category name.
* Otherwise works just like getMutable(Category, UErrorCode &).
* reports an error if the category name is invalid.
*/
T *getMutable(
const char *category,
UErrorCode &status) {
return getMutable(toCategory(category), nullptr, status);
}
/**
* Just like getMutable(Category, UErrorCode &) but copies defaultValue to
* returned pointer if it was defaulting to the 'other' variant
* because no explicit value was stored.
*/
T *getMutableWithDefault(
Category category,
const T &defaultValue,
UErrorCode &status) {
return getMutable(category, &defaultValue, status);
}
/**
* Returns true if this object equals rhs.
*/
UBool equals(
const PluralMap<T> &rhs,
UBool (*eqFunc)(const T &, const T &)) const {
for (int32_t i = 0; i < UPRV_LENGTHOF(fVariants); ++i) {
if (fVariants[i] == rhs.fVariants[i]) {
continue;
}
if (fVariants[i] == nullptr || rhs.fVariants[i] == nullptr) {
return false;
}
if (!eqFunc(*fVariants[i], *rhs.fVariants[i])) {
return false;
}
}
return true;
}
private:
T fOtherVariant;
T* fVariants[6];
T *getMutable(
Category category,
const T *defaultValue,
UErrorCode &status) {
if (U_FAILURE(status)) {
return nullptr;
}
int32_t index = category;
if (index < 0 || index >= UPRV_LENGTHOF(fVariants)) {
status = U_ILLEGAL_ARGUMENT_ERROR;
return nullptr;
}
if (fVariants[index] == nullptr) {
fVariants[index] = defaultValue == nullptr ?
new T() : new T(*defaultValue);
}
if (!fVariants[index]) {
status = U_MEMORY_ALLOCATION_ERROR;
}
return fVariants[index];
}
void initializeNew() {
fVariants[0] = &fOtherVariant;
for (int32_t i = 1; i < UPRV_LENGTHOF(fVariants); ++i) {
fVariants[i] = nullptr;
}
}
};
U_NAMESPACE_END
#endif