log4cpp单例类封装

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github源码地址：https://github.com/meihao1203/log4cpp

#ifndef __MYLOG_H__

#define __MYLOG_H__

#include<iostream>

#include<log4cpp/Category.hh>

#include<log4cpp/Appender.hh>

#include<log4cpp/OstreamAppender.hh>

#include<log4cpp/FileAppender.hh>

#include<log4cpp/RollingFileAppender.hh>

#include<log4cpp/PatternLayout.hh>

#include<log4cpp/Priority.hh>

#include<string>

#include<sstream>

using namespace std;

//using namespace log4cpp;   //为了程序可读性好,下面都自己加上作用域限定

//单例类封装log4cpp

enum myPriority{EMERG,FATAL,ALERT,CRIT,ERROR,WARN,NOTICE,INFO,DEBUG};

class myLog

{

        public:

                static myLog* getInstance();  

                static void destroy();

                void setPriority(myPriority priority);   //myPriority 我把它定义为一种enum类型

                void fatal(const char* msg);

                void error(const char* msg);

                void warn(const char* msg);

                void info(const char* msg);

                void debug(const char* msg);

        private:

                static myLog* _plog;

                log4cpp::Category& rootCategory;

        private:

                myLog();

                ~myLog();

};

/***********************实现(方便引用，就不单独放到一个文件中了)***********************/

myLog* myLog::_plog = NULL;  //静态成员初始化

//构造函数

myLog::myLog():rootCategory(log4cpp::Category::getRoot().getInstance("rootCategory"))

{

        //获取根Category，引用成员必须在成员初始化列表初始化

        //根Category下添加子Category

        log4cpp::OstreamAppender* osAppender = new log4cpp::OstreamAppender("osAppender",&cout);

        log4cpp::PatternLayout* pLayout1 = new log4cpp::PatternLayout();

        pLayout1->setConversionPattern("%d: %p %c %x: %m%n");

        osAppender->setLayout(pLayout1);

        rootCategory.addAppender(osAppender);

        rootCategory.setPriority(log4cpp::Priority::DEBUG);

        //mylog.log会一直记录

        log4cpp::FileAppender* fileAppender = new log4cpp::FileAppender("fileAppender","log");

        log4cpp::PatternLayout* pLayout2 = new log4cpp::PatternLayout();

        pLayout2->setConversionPattern("%d: %p %c %x: %m%n");

        fileAppender->setLayout(pLayout2);

        rootCategory.addAppender(fileAppender);

        rootCategory.setPriority(log4cpp::Priority::DEBUG);

        //mylogrolling.log不超过指定大小，默认10M；这里我设置了5M,备份文件5个

//如果想要用备份带回卷的日志文件记录方式，就把这里的注释去掉

//        log4cpp::RollingFileAppender* rollingfileAppender = new log4cpp::RollingFileAppender(

//                        "rollingfileAppender","logrolling.log",5*1024,5);

//        log4cpp::PatternLayout* pLayout3 = new log4cpp::PatternLayout();

//        pLayout3->setConversionPattern("%d: %p %c %x: %m%n");

//        rollingfileAppender->setLayout(pLayout3);

//        rootCategory.addAppender(rollingfileAppender);

//        rootCategory.setPriority(log4cpp::Priority::DEBUG);

        rootCategory.info("myLog()");

}

inline myLog::~myLog()

{

        rootCategory.info("~mylog()");

        rootCategory.shutdown();  

}

inline void myLog::destroy()

{

        _plog->rootCategory.info("myLog destroy");   //静态函数内部没有隐士传递的this指针，所以必须要用_plog对象指针来调用

        delete _plog;   //delete的处理方式是：先调用析构函数，然后在释放空间；

        //所以可以在析构函数里再向日志里打印信息，然后再关掉rootCategory

}

inline myLog* myLog::getInstance()

{

        if(NULL==_plog)

        {

                _plog = new myLog();

        }

        return _plog;

}

//类对象调用,重新设置rootCategory优先级

inline void myLog::setPriority(myPriority priority)

{

        switch(priority)

        {

                case FATAL:rootCategory.setPriority(log4cpp::Priority::FATAL);break;

                case ERROR:rootCategory.setPriority(log4cpp::Priority::ERROR);break;

                case WARN:rootCategory.setPriority(log4cpp::Priority::WARN);break;

                case INFO:rootCategory.setPriority(log4cpp::Priority::INFO);break;

                case DEBUG:rootCategory.setPriority(log4cpp::Priority::DEBUG);break;

                default:

                           rootCategory.setPriority(log4cpp::Priority::DEBUG);break;

        }

}

inline void myLog::error(const char* msg)

{

        rootCategory.error(msg);

}

inline void myLog::warn(const char* msg)

{

        rootCategory.warn(msg);

}

inline void myLog::info(const char* msg)

{

        rootCategory.info(msg);

}

inline void myLog::debug(const char* msg)

{

        rootCategory.debug(msg);

}

inline void myLog::fatal(const char* msg)

{

        rootCategory.fatal(msg);

}

/***********************myLog类定义完毕***********************/

/***********************定义一些宏，引用的时候直接展开，让myLog使用更方便***********************/

//把要输出的消息拼接上文件名，所在函数名，所在行号;msg是const char*，所以最后用c_str()函数

//__FILE__ __func__ __LINE 这几个宏定义是编译器识别的，__LINE__是int形

//分别是文件名，函数名，所在行号

//防止在函数中调用，声明成内联函数

inline string int2string(int lineNumber)

{

        ostringstream oss;

        oss<<lineNumber;

        return oss.str();

}

#define catMsg(msg) string(msg).append(" {fileName:")\

        .append(__FILE__).append(" functionName:")\

        .append(__func__).append(" lineNumber:")\

        .append(int2string(__LINE__)).append("}").c_str()

//单例类，只有一个对象

myLog* log  = myLog::getInstance();

#define logSetpriority(priority) log->setPriority(priority)

#define logError(msg) log->error(catMsg(msg))

#define logWarn(msg) log->warn(catMsg(msg))

#define logInfo(msg) log->info(catMsg(msg))

#define logDebug(msg) log->debug(catMsg(msg))

#define logFatal(msg) log->fatal(catMsg(msg))

#define logDestroy() myLog::destroy()

#endif

#include"myLog.h"

#include<iostream>

using namespace std;

void func()

{

        logInfo("this is a function");

}

int main()

{

        logInfo("system is running");

        logWarn("system has a warning");

        logError("system has a error");

        logFatal("system has a fatal");

        logSetpriority(ERROR);  //重新设置优先级

        logWarn("warn again");  //Warn的优先级小于ERROR,这条信息将不会被记录

        logSetpriority(DEBUG);  //为了记录下面代码的日志信息,INFO的优先级也是小于ERROR的

        func();

        logDestroy();    //程序结束，销毁myLog对象

        return 0;

}