/**
* @file validator.h
* @author your name (you@domain.com)
* @brief 观察者模式 Visitor Pattern 来源： C现代编程 集成开发环境、设计模式、极限编程、测试驱动开发、重构、持续集成 日.花井志生著，杨文轩译，人民邮电出版社
* @version 0.1
* @date 2023-10-21
*
* @copyright Copyright (c) 2023
*
*/
#ifndef _VALIDATOR_H_
#define _VALIDATOR_H_
#include <stddef.h>
#include <stdbool.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief
*
*/
struct ValidatorVisitor;
/**
* @brief
*
*/
typedef struct Validator {
bool (* const validate)(struct Validator *pThis, int val);
void (* const accept)(struct Validator *pThis, struct ValidatorVisitor *pVisitor);
} Validator;
/**
* @brief
*
*/
typedef struct {
Validator base;
const int min;
const int max;
} RangeValidator;
/**
* @brief
*
*/
typedef struct {
Validator base;
int previousValue;
} PreviousValueValidator;
/**
* @brief
*
*/
typedef struct ValidatorVisitor {
void (* const visitRange)(struct ValidatorVisitor *pThis, RangeValidator *p);
void (* const visitPreviousValue)(struct ValidatorVisitor *pThis, PreviousValueValidator *p);
} ValidatorVisitor;
/**
* @brief
*
* @param pThis
* @param pVisitor
*/
void acceptRange(Validator *pThis, ValidatorVisitor *pVisitor);
/**
* @brief
*
* @param pThis
* @param pVisitor
*/
void acceptPrevious(Validator *pThis, ValidatorVisitor *pVisitor);
/**
* @brief
*
* @param pThis
* @param val
* @return true
* @return false
*/
bool validateRange(Validator *pThis, int val);
/**
* @brief
*
* @param pThis
* @param val
* @return true
* @return false
*/
bool validatePrevious(Validator *pThis, int val);
/**
* @brief
*
*/
#define newRangeValidator(min, max) \
{{validateRange, acceptRange}, (min), (max)}
/**
* @brief
*
*/
#define newPreviousValueValidator \
{{validatePrevious, acceptPrevious}, 0}
#ifdef __cplusplus
}
#endif
#endif
/**
* @file validator.c
* @author your name (you@domain.com)
* @brief 观察者模式 Visitor Pattern 来源： C现代编程 集成开发环境、设计模式、极限编程、测试驱动开发、重构、持续集成 日.花井志生著，杨文轩译，人民邮电出版社
* @version 0.1
* @date 2023-10-21
*
* @copyright Copyright (c) 2023
*
*/
#include <stdbool.h>
#include <stdio.h>
#include "include/validator.h"
/**
* @brief
*
* @param p
* @param val
* @return true
* @return false
*/
bool validateRange(Validator *p, int val) {
RangeValidator *pThis = (RangeValidator *)p;
return pThis->min <= val && val <= pThis->max;
}
/**
* @brief
*
* @param p
* @param val
* @return true
* @return false
*/
bool validatePrevious(Validator *p, int val) {
PreviousValueValidator *pThis = (PreviousValueValidator *)p;
if (val < pThis->previousValue) return false;
pThis->previousValue = val;
return true;
}
/**
* @brief
*
* @param p
* @param pVisitor
*/
void acceptRange(Validator *p, ValidatorVisitor *pVisitor) {
pVisitor->visitRange(pVisitor, (RangeValidator *)p);
}
/**
* @brief
*
* @param p
* @param pVisitor
*/
void acceptPrevious(Validator *p, ValidatorVisitor *pVisitor) {
pVisitor->visitPreviousValue(pVisitor, (PreviousValueValidator *)p);
}
/**
* @file validatorView.h
* @author your name (you@domain.com)
* @brief 观察者模式 Visitor Pattern 来源： C现代编程 集成开发环境、设计模式、极限编程、测试驱动开发、重构、持续集成 日.花井志生著，杨文轩译，人民邮电出版社
* @version 0.1
* @date 2023-10-21
*
* @copyright Copyright (c) 2023
*
*/
#ifndef _VALIDATORVIEW_H_
#define _VALIDATORVIEW_H_
#include <stddef.h>
#include <stdbool.h>
#include <stdlib.h>
#include "validator.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief
*
* @param p
* @param pBuf
* @param size
*/
void printValidator(const Validator *p, char *pBuf, size_t size);
#ifdef __cplusplus
}
#endif
#endif
/**
* @file validatorView.c
* @author your name (you@domain.com)
* @brief 观察者模式 Visitor Pattern 来源： C现代编程 集成开发环境、设计模式、极限编程、测试驱动开发、重构、持续集成 日.花井志生著，杨文轩译，人民邮电出版社
* @version 0.1
* @date 2023-10-21
*
* @copyright Copyright (c) 2023
*
*/
#include <stdio.h>
#include "include/validator.h"
/**
* @brief
*
* @param pThis
* @param p
*/
static void rangeView(ValidatorVisitor *pThis, RangeValidator *p);
/**
* @brief
*
* @param pThis
* @param p
*/
static void previousValueView(ValidatorVisitor *pThis, PreviousValueValidator *p);
/**
* @brief
*
*/
typedef struct ViewVisitor {
ValidatorVisitor base;
char *pBuf;
size_t size;
} ViewVisitor;
/**
* @brief
*
* @param p
* @param pBuf
* @param size
*/
void printValidator(Validator *p, char *pBuf, size_t size) {
ViewVisitor visitor = {{rangeView, previousValueView}, pBuf, size};
p->accept(p, &visitor.base);
}
/**
* @brief
*
* @param pThis
* @param p
*/
static void rangeView(ValidatorVisitor *pThis, RangeValidator *p) {
ViewVisitor *pVisitor = (ViewVisitor* )pThis;
snprintf(pVisitor->pBuf, pVisitor->size, "Range(%d-%d)", p->min, p->max);
}
/**
* @brief
*
* @param pThis
* @param p
*/
static void previousValueView(ValidatorVisitor *pThis, PreviousValueValidator *p) {
ViewVisitor *pVisitor = (ViewVisitor* )pThis;
snprintf(pVisitor->pBuf, pVisitor->size, "Previous");
}
调用：
#include "include/validator.h"
#include "include/validatorView.h"
int main()
{
printf("hello c world, \n");
printf("你好，中国\n");
RangeValidator v = newRangeValidator(0, 9);
char buf[32];
printValidator(&v.base, buf, sizeof(buf));
strcmp("Range(0-9)", buf);
printf("观察者模式1: %s\n",buf);
PreviousValueValidator v2 = newPreviousValueValidator;
char buf2[32];
printValidator(&v2.base, buf2, sizeof(buf2));
strcmp("Previous", buf2);
printf("观察者模式1: %s\n",buf2);
return 0;
}
