东西写的太简单了 都不好意思说是NOSQL
其实就是STL 的map容器记录了写入的信息
解析了下数据仅此。
分析的时候想了很多
比如学习redis的自写hash，动态调整hash表容量。
比如右值或者C语言直接操作内存 提升效率
比如多线程操作互斥 网络连接 记录操作时间等等
但是c++写起来，心智负担太多。
实在是太繁琐 一点激情都没了
还是简单一点 写个完整的获益更多。
最后就是这个简单完整的小代码
#include <iostream>
#include <unordered_map>
#include <string>
#include <map>
#include <vector>
#include <assert.h>
using namespace std; enum Command{
AddKeyValue = 101,
GetKeyValue,
SetValue,
ReplaceValue,
DeleteKeyValue,
AppendValue,
PreappendValue,
InvalidCommand
}; enum TokenVecIndex{
commandIndex = 0,
keyIndex,
valueIndex,
invalidIndex
}; std::unordered_map<std::string,Command> CommandString =
{
{"add",AddKeyValue},
{"get",GetKeyValue},
{"set",SetValue},
{"replace",ReplaceValue},
{"del",DeleteKeyValue},
{"append",AppendValue},
{"preapp",PreappendValue}
}; std::unordered_map<std::string,std::string> ItemHashStorage; void splitWithSTLFind(const string& str, const string& delim, vector<string>& ret)
{
size_t front = str.find_first_not_of(delim);
size_t back = str.find_first_of(delim, front) ; while(back != std::string::npos &&
front != std::string::npos){
ret.emplace(ret.end(),str.substr(front, back - front));
front = str.find_first_not_of(delim, back +1);
back = str.find_first_of(delim, front);
}
if(front != std::string::npos){
ret.emplace(ret.end(),str.substr(front, back - front));
}
} bool CheckToken(std::vector<std::string>& tokenVec)
{
bool bRet = false; if( (tokenVec[commandIndex] == "get" || tokenVec[commandIndex] == "del")
&& tokenVec.size() != 2){
return bRet;
} if(tokenVec.size() != 3)
return bRet; bRet = true;
return bRet;
} bool GetCommand(const std::string& input,std::vector<std::string>& tokenVec){
std::string delim = " ";
tokenVec.clear();
splitWithSTLFind(input,delim,tokenVec);
return CheckToken(tokenVec);
} bool SetValueFunc(const std::vector<std::string>& tokenVec){
ItemHashStorage[tokenVec[keyIndex]] = tokenVec[valueIndex];
return true;
} bool AddKeyValueFunc(const std::vector<std::string>& tokenVec){
if( ItemHashStorage.find(tokenVec[keyIndex]) != ItemHashStorage.end())
return true;
SetValueFunc(tokenVec);
return true;
} bool ReplaceValueFunc(const std::vector<std::string>& tokenVec){
if( ItemHashStorage.find(tokenVec[keyIndex]) == ItemHashStorage.end())
return false;
SetValueFunc(tokenVec);
return true;
} bool GetKeyValueFunc(const std::vector<std::string>& tokenVec,string& retValueString){
auto it = ItemHashStorage.find(tokenVec[keyIndex]);
if( it == ItemHashStorage.end())
return false;
retValueString = it->second;
return true;
} bool PreappendValueFunc(const std::vector<std::string>& tokenVec){
auto it = ItemHashStorage.find(tokenVec[keyIndex]);
if( it == ItemHashStorage.end())
return false;
string s = tokenVec[valueIndex];
s.append(it->second);
std::swap(s,it->second);
return true;
} bool DeleteKeyValueFunc(const std::vector<std::string>& tokenVec){
auto it = ItemHashStorage.find(tokenVec[keyIndex]);
if( it == ItemHashStorage.end())
return true;
ItemHashStorage.erase(it);
return true;
} bool AppendValueFunc(const std::vector<std::string>& tokenVec){
auto it = ItemHashStorage.find(tokenVec[keyIndex]);
if( it == ItemHashStorage.end())
return false;
(it->second).append(tokenVec[valueIndex]);
return true;
} bool Excute(const std::vector<std::string>& tokenVec,string& retValueString){
bool bRet = false;
auto it = CommandString.find(tokenVec[commandIndex]);
if( it == CommandString.end())
return bRet;
switch(it->second){
case AddKeyValue:
bRet = AddKeyValueFunc(tokenVec);
break;
case GetKeyValue:
bRet = GetKeyValueFunc(tokenVec,retValueString);
break;
case SetValue:
bRet = SetValueFunc(tokenVec);
break;
case ReplaceValue:
bRet = ReplaceValueFunc(tokenVec);
break;
case DeleteKeyValue:
bRet = DeleteKeyValueFunc(tokenVec);
break;
case AppendValue:
bRet = AppendValueFunc(tokenVec);
break;
case PreappendValue:
bRet = PreappendValueFunc(tokenVec);
break;
default:
break;
} return bRet;
} std::vector<std::string> testStringVec1={
" add ",
" add testkey1 testvalue1",
" add testkey1 testvalue1",
" add testkey1 testvalue1",
" add"
}; std::vector<std::string> testStringVec2={
" add ",
" add testkey2 testvalue1",
" add testkey3 testvalue1",
" add testkey4 testvalue1",
" add"
}; int main(int argc, char *argv[])
{
// test
for(auto it:testStringVec1 ){
std::vector<std::string> tokenVec;
if( GetCommand(it,tokenVec)){
std::string s;
Excute(tokenVec,s);
}
}
assert(ItemHashStorage.size()==1); for(auto it:testStringVec2 ){
std::vector<std::string> tokenVec;
if( GetCommand(it,tokenVec)){
std::string s;
Excute(tokenVec,s);
}
}
assert(ItemHashStorage.size()==4); {
std::vector<std::string> tokenVec;
string commandStr= "get testkey4";
string s;
GetCommand(commandStr,tokenVec);
Excute(tokenVec,s);
assert(s==string("testvalue1"));
} {
std::vector<std::string> tokenVec;
string commandStr= "get testkey4 testkey4";
string s;
GetCommand(commandStr,tokenVec);
Excute(tokenVec,s);
assert(s==string("testvalue1"));
} {
std::vector<std::string> tokenVec;
string commandStr= "get nothing testkey4";
string s;
GetCommand(commandStr,tokenVec);
assert( false == Excute(tokenVec,s));
assert(s == string(""));
} {
std::vector<std::string> tokenVec;
string commandStr= "set testkey2 testkey4";
string s;
GetCommand(commandStr,tokenVec);
Excute(tokenVec,s);
GetCommand("get testkey2",tokenVec);
Excute(tokenVec,s);
assert(s == ("testkey4"));
} {
std::vector<std::string> tokenVec;
string commandStr= "replace testkey3 testkey33";
string s;
GetCommand(commandStr,tokenVec);
Excute(tokenVec,s);
GetCommand("get testkey3",tokenVec);
Excute(tokenVec,s);
assert(s == ("testkey33"));
} {
std::vector<std::string> tokenVec;
string commandStr= "del testkey3 testkey33";
string s;
GetCommand(commandStr,tokenVec);
assert(Excute(tokenVec,s));
GetCommand("get testkey3",tokenVec);
assert(false == Excute(tokenVec,s));
assert(s== (""));
} {
std::vector<std::string> tokenVec;
string commandStr= "append testkey1 -appendValue";
string s;
GetCommand(commandStr,tokenVec);
assert(Excute(tokenVec,s));
GetCommand("get testkey1",tokenVec);
assert(Excute(tokenVec,s));
assert(s== "testvalue1-appendValue");
} {
std::vector<std::string> tokenVec;
string commandStr= "preapp testkey1 Pre-";
string s;
GetCommand(commandStr,tokenVec);
assert(Excute(tokenVec,s));
GetCommand("get testkey1",tokenVec);
assert(Excute(tokenVec,s));
assert(s== "Pre-testvalue1-appendValue");
}
return 0;
}