【云备份|| 日志 day2】FileUtil JsonUtil-编程知识

这几天感冒了，稍微落下了进度

在这里插入图片描述

util工具

fileUtil（文件操作类）

在客户端，又或者是在服务端，本质是都是对文件的读写和管理，所以有必要封装一个文件操作类。

class FileUtil{
private:std::string _name;
public:FileUtil(const std::string &name);size_t FileSize();// 文件大小time_t LastATime(); // 最后一次查看文件时间time_t LastMTime(); // 最后一次修改文件的时间std::string FileName();   //文件名字bool GetPosLen(std::string *content, size_t pos, size_t len);  //获取文件流pos 后len个长度的数据bool GetContent(std::string *content);  //获取文件内容bool SetContent(std::strint *content);   //写入文件bool Compress(const std::string &packname);   //压缩文件bool UnCompress(const std::string &filename);  //解压文件bool Exists();     //判断文件是否存在bool CreateDirectory();    //创建一个目录bool ScanDirectory(std::vector<std::string> *arry);  //查看目录下的文件内容}

JsonUtil

服务端和客户端进行对话，传输数据，一定要跨网络传输，就一定需要将数据序列化（Serialize）和反序列化（UnSerialize）。

class JsonUtil{
public:static bool Serialize(const Json::Value &root, std::string *str);  //序列化static bool UnSerialize(const std::string &str, Json::Value *root);   //反序列化
};

注意：
编译时，我们需要链接第三方库

-lpthread -lstdc++fs -ljsoncpp -lbundle

-lpthread ，-lbundle： bundle.h中调用了线程库，所以需要链接。

-lstdc++fs ：文件中关于目录部分的函数编写调用了filesystem中的函数。

-ljsoncpp ：序列和反序列化时需要。

代码：

#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <experimental/filesystem>
#include <sys/stat.h>
#include <jsoncpp/json/json.h>
#include "bundle.h"namespace cloud{namespace fs = std::experimental::filesystem;class FileUtil{private:std::string _filename;public:FileUtil(const std::string &filename):_filename(filename){}bool Remove(){if (this->Exists()== false) {return true;}remove(_filename.c_str());return true;}int64_t FileSize(){struct stat st;if (stat(_filename.c_str(), &st) < 0) {std::cout << "get file size failed!\n";return -1;}return st.st_size;}time_t LastMTime(){struct stat st;if (stat(_filename.c_str(), &st) < 0) {std::cout << "get file size failed!\n";return -1;}return st.st_mtime;}time_t LastATime() {struct stat st;if (stat(_filename.c_str(), &st) < 0) {std::cout << "get file size failed!\n";return -1;}return st.st_atime;}std::string FileName(){// ./abc/test.txtsize_t pos = _filename.find_last_of("/");if (pos == std::string::npos) {return _filename;}return _filename.substr(pos+1);}bool GetPosLen(std::string *body, size_t pos, size_t len){size_t fsize = this->FileSize();if (pos + len > fsize){std::cout << "get file len is error\n";return false;}std::ifstream ifs;ifs.open(_filename, std::ios::binary);if (ifs.is_open() == false) {std::cout << "read open file failed!\n";return false;}ifs.seekg(pos, std::ios::beg);body->resize(len);ifs.read(&(*body)[0], len);if (ifs.good() == false) {std::cout << "get file content failed\n";ifs.close();return false;}ifs.close();return true;}bool GetContent(std::string *body) {size_t fsize = this->FileSize();return GetPosLen(body, 0, fsize);}bool SetContent(const std::string &body) {std::ofstream ofs;ofs.open(_filename, std::ios::binary);if (ofs.is_open() == false) {std::cout << "write open file failed!\n";return false;}ofs.write(&body[0], body.size());if (ofs.good() == false) {std::cout << "write file content failed!\n";ofs.close();return false;}ofs.close();return true;}bool Compress(const std::string &packname){//1. 获取源文件数据std::string body;if (this->GetContent(&body) == false){std::cout << "compress get file content failed!\n";return false;}//2. 对数据进行压缩std::string packed = bundle::pack(bundle::LZIP, body);//3. 将压缩的数据存储到压缩包文件中FileUtil fu(packname);if (fu.SetContent(packed) == false){std::cout << "compress write packed data failed!\n";return false;}return true;}bool UnCompress(const std::string &filename) {//将当前压缩包数据读取出来std::string body;if (this->GetContent(&body) == false){std::cout << "uncompress get file content failed!\n";return false;}//对压缩的数据进行解压缩std::string unpacked = bundle::unpack(body);//将解压缩的数据写入到新文件FileUtil fu(filename);if (fu.SetContent(unpacked) == false){std::cout << "uncompress write packed data failed!\n";return false;}return true;}bool Exists() {return fs::exists(_filename);}bool CreateDirectory() {if (this->Exists()) return true;return fs::create_directories(_filename);}bool ScanDirectory(std::vector<std::string> *arry) {for(auto& p: fs::directory_iterator(_filename)) {if (fs::is_directory(p) == true){continue;}//relative_path 带有路径的文件名arry->push_back(fs::path(p).relative_path().string());}return true;}};class JsonUtil{public:static bool Serialize(const Json::Value &root, std::string *str){Json::StreamWriterBuilder swb;std::unique_ptr<Json::StreamWriter> sw(swb.newStreamWriter());std::stringstream ss; if (sw->write(root, &ss) != 0) {std::cout << "json write failed!\n";return false;}*str = ss.str();return true;}static bool UnSerialize(const std::string &str, Json::Value *root){Json::CharReaderBuilder crb;std::unique_ptr<Json::CharReader> cr(crb.newCharReader());std::string err;bool ret = cr->parse(str.c_str(), str.c_str() + str.size(), root, &err);if (ret == false) {std::cout << "parse error: " << err << std::endl;return false; }return true;}};
}