参考：muduo库以及http://blog.csdn.net/ygm_linux/article/details/25690829
Timestamp.h
#ifndef MUDUO_BASE_TIMESTAMP_H
#define MUDUO_BASE_TIMESTAMP_H
#include <boost/operators.hpp>
#include <iostream>
#include <string>
using namespace std;
namespace muduo
{
class copyable
{
};
class Timestamp : public copyable,
public boost::less_than_comparable<Timestamp>
{
public:
///
/// Constucts an invalid Timestamp.
///
Timestamp()
: microSecondsSinceEpoch_(0)
{
}
///
/// Constucts a Timestamp at specific time
///
/// @param microSecondsSinceEpoch
explicit Timestamp(int64_t microSecondsSinceEpoch);
void swap(Timestamp& that)
{
std::swap(microSecondsSinceEpoch_, that.microSecondsSinceEpoch_);
}
// default copy/assignment/dtor are Okay
string toString() const;
string toFormattedString() const;
bool valid() const { return microSecondsSinceEpoch_ > 0; }
// for internal usage.
int64_t microSecondsSinceEpoch() const { return microSecondsSinceEpoch_; }
time_t secondsSinceEpoch() const
{ return static_cast<time_t>(microSecondsSinceEpoch_ / kMicroSecondsPerSecond); }
///
/// Get time of now.
///
static Timestamp now();
static Timestamp invalid();
static const int kMicroSecondsPerSecond = 1000 * 1000;
private:
int64_t microSecondsSinceEpoch_;
};
inline bool operator<(Timestamp lhs, Timestamp rhs)
{
return lhs.microSecondsSinceEpoch() < rhs.microSecondsSinceEpoch();
}
inline bool operator==(Timestamp lhs, Timestamp rhs)
{
return lhs.microSecondsSinceEpoch() == rhs.microSecondsSinceEpoch();
}
///
/// Gets time difference of two timestamps, result in seconds.
///
/// @param high, low
/// @return (high-low) in seconds
/// @c double has 52-bit precision, enough for one-microseciond
/// resolution for next 100 years.
inline double timeDifference(Timestamp high, Timestamp low)
{
int64_t diff = high.microSecondsSinceEpoch() - low.microSecondsSinceEpoch();
return static_cast<double>(diff) / Timestamp::kMicroSecondsPerSecond;
}
///
/// Add @c seconds to given timestamp.
///
/// @return timestamp+seconds as Timestamp
///
inline Timestamp addTime(Timestamp timestamp, double seconds)
{
int64_t delta = static_cast<int64_t>(seconds * Timestamp::kMicroSecondsPerSecond);
return Timestamp(timestamp.microSecondsSinceEpoch() + delta);
}
}
#endif
Timestamp.cpp
#include <boost/static_assert.hpp>
#include <sys/time.h>
#include <stdio.h>
#include "Timestamp.h"
/*
http://blog.csdn.net/ygm_linux/article/details/25899385
跨平台的:64位整数
*/
#define __STDC_FORMAT_MACROS
#include <inttypes.h>
//PRId64
#undef __STDC_FORMAT_MACROS
using namespace muduo;
BOOST_STATIC_ASSERT(sizeof(Timestamp) == sizeof(int64_t));
/*
以微秒初始化microSecondsSinceEpoch_
*/
Timestamp::Timestamp(int64_t microseconds)
: microSecondsSinceEpoch_(microseconds)
{
}
/*
将微秒microSecondsSinceEpoch_ 转换为[秒seconds + 微秒microseconds]
*/
string Timestamp::toString() const
{
char buf[32] = {0};
int64_t seconds = microSecondsSinceEpoch_ / kMicroSecondsPerSecond;
int64_t microseconds = microSecondsSinceEpoch_ % kMicroSecondsPerSecond;
snprintf(buf, sizeof(buf)-1, "%" PRId64 ".%06" PRId64 "", seconds, microseconds);
return buf;
}
/*
将微秒microSecondsSinceEpoch_ 转换为[time_t]
http://blog.csdn.net/csuwzc/article/details/6912104
再利用gmtime_r 将time_t 时间做转换存于 tm_time
*/
string Timestamp::toFormattedString() const
{
char buf[32] = {0};
time_t seconds = static_cast<time_t>(microSecondsSinceEpoch_ / kMicroSecondsPerSecond);
int microseconds = static_cast<int>(microSecondsSinceEpoch_ % kMicroSecondsPerSecond);
struct tm tm_time;
gmtime_r(&seconds, &tm_time);
snprintf(buf, sizeof(buf), "%4d%02d%02d %02d:%02d:%02d.%06d",
tm_time.tm_year + 1900, tm_time.tm_mon + 1, tm_time.tm_mday,
tm_time.tm_hour, tm_time.tm_min, tm_time.tm_sec,
microseconds);
return buf;
}
/*
将当前时间以微秒存Timestamp类的变量microSecondsSinceEpoch 中;
调用explicit Timestamp(int64_t) 返回
*/
Timestamp Timestamp::now()
{
struct timeval tv;
gettimeofday(&tv, NULL);
int64_t seconds = tv.tv_sec;
return Timestamp(seconds * kMicroSecondsPerSecond + tv.tv_usec);
}
/*
将0 存Timestamp类的变量microSecondsSinceEpoch 中;
调用Timestamp() 返回
*/
Timestamp Timestamp::invalid()
{
return Timestamp();
}
test.cpp
#include <vector>
#include <stdio.h>
#include "Timestamp.h"
using muduo::Timestamp;
void benchmark()
{
/*
获得1000*1000次时间存于vector 中
*/
const int kNumber = 1000*1000;
std::vector<Timestamp> stamps;
stamps.reserve(kNumber);
for (int i = 0; i < kNumber; ++i)
{
stamps.push_back(Timestamp::now());
}
/*
打印第一次和最后一次获得的时间的差
*/
printf("%s\n", stamps.front().toString().c_str());
printf("%s\n", stamps.back().toString().c_str());
printf("%f\n", timeDifference(stamps.back(), stamps.front()));
printf("===================\n");
/*
start为上次时间的微妙数,
next为下次时间的微妙数,
inc 表示时间差next - start;
统计前后时间差为index (<100微妙)出现的次数
increments[index]
*/
int increments[100] = { 0 };
int64_t start = stamps.front().microSecondsSinceEpoch();
for (int i = 1; i < kNumber; ++i)
{
int64_t next = stamps[i].microSecondsSinceEpoch();
int64_t inc = next - start;
start = next;
if (inc < 0)
{
printf("reverse!\n");
}
else if (inc < 100)
{
++increments[inc];
}
else
{
printf("big gap %d\n", static_cast<int>(inc));
}
}
/*
获得的1000*1000 次时间,前后的时间差值为inc 微妙,
increments[inc] 即为出现inc< 100 的次数
*/
for (int i = 0; i < 100; ++i)
{
printf("%2d: %d\n", i, increments[i]);
}
}
int main()
{
Timestamp now(Timestamp::now());
//
输出当前时间的微妙
printf("%s\n", now.toString().c_str());
printf("===================\n");
/*
统计可知基本获得的连续的时间差在100微妙以内
*/
benchmark();
}
摘要：有的同学对数字签名的认知还不是那么到位，所以签名
时
的每一个参数具体意义还不了解的情况下就开始签名。这种情况下，还会导致很多错误，其中常见的错误是
时
间戳错误（Invalid
TimeStamp
.Expired），本文教给您解决方法。
今天做微信支付,js版本的，是基于官方提供的php sdk
正确配置完后，点击支付，提示
timeStamp
invalid,起初以为是本地
时
间和服务器
时
间不一致，所以重启校准了一下
时
间，但还是有问题，于是查看sdk代码，在WxPay.jsApiPay.php的GetJsApiParameters中看到
timeStamp
参数。
$
timeStamp
= time();
后来查看文档
作者：梁敏之前在win7上打包windows程序版本
时
，偶尔会遇到签名
时
间戳会失败的场景。之前解决方法一般是多试一次，或者尝试换一个
时
间戳服务器就可以了。最近版本提测上线，在使用win7打包版本
时
，总是签名
时
间戳失败了，几乎是每次都不行。但是尝试替换各种服务器，还是不行。另外使用wosigncode.exe的工具，使用相同的
时
间戳服务器，都是可以成功的。说明不是
时
间戳服务器的问题。记得之前的项目打...
timestamp
默认值 '0000-00-00 00:00:00' ERROR 1067 (42000): Invalid default value for 'XXX'
`created_time`
timestamp
NOT NULL DEFAULT '0000-00-00 00:00:00' COMMENT '插入
时
间',
SE...
TIMESTAMP
的变体
1，
TIMESTAMP
DEFAULT CURRENT_
TIMESTAMP
ON UPDATE CURRENT_
TIMESTAMP
在创建新记录和修改现有记录的
时
候都对这个数据列刷新
2，
TIMESTAMP
DEFAULT CURRENT_
TIMESTAMP
在创建新记录的
时
候把这个
字段设置为当前
时
间，但以后修改
时
，不再刷新它
3，TIMES
如图配置两个参数：
url：配置一个后台接口，微信会带4个参数访问这个接口，后台需要拿到参数做验证后返回参数中的echostr才能验证成功
token: 自定义的字符串，后台做验证
时
需要用到
如图配置的话微信的访问链接如下：
245691q6b5.zicp.vip/wx?signatur…
//http://245691q6b5.zicp.vi...
总结之前项目出现得问题，第一次在linux上运行项目，服务器运行成功之后访问项目，别得都好好得，就登陆
时
候得验证码获得不了，使用谷歌浏览器的Network监测到请求已经发过去了，然后直接调用获取验证码的方法报错：“java.lang.NoClassDefFoundError:could not initialise class sun.awt.X11FontManager”。
然后又去百度，什么...
