«Нет соответствующего конструктора по умолчанию» Я искал всюду для ответа

Question

Я просмотрел все сообщения по этой теме, и ни один из них не является полезным. ПОЖАЛУЙСТА, помогите моему назначению выступить через два часа.

Здесь пока соответствующий заголовок

class RCB { 
private: 
    str     rID; 
    int     numResources; 
    int     availableResources; 
    int     resourcesRequested;  //The amount of resources requested including resources requested from PCB's in the waitlist 


public: 

    std::list<PCB*>  waitList; 

    RCB(str name, int r); 
    ~RCB(); 

    void setRID(str name) { rID = name; } 
    void allocateResources(int n) { availableResources -= n; } 
    void returnResources(int n) { availableResources += n; } 

    int getNumResources(){ return numResources; } 
    int getAvailableResources(){ return availableResources; } 
    str getRID(){ return rID; } 
    int getResourcesRequested() { return resourcesRequested; } 

}; 

А вот Исходный файл

RCB::RCB(str name, int r) : 
     rID{ name }, 
     numResources{ r }, 
     availableResources{ r }, 
     resourcesRequested{ 0 } 
    {} 

Я получаю ошибку

Ошибка 1 Ошибка C2512: 'RCB': нет необходимости конструктор по умолчанию доступно c: \ program files (x86) \ microsoft visual studio 12.0 \ vc \ include \ tuple 746 1 ProcessScheduler

Вот остальная часть источника

#include "Data.h" 



PCB::PCB(str name, int p) : 
    pID{ name }, 
    status{ READY }, 
    backptr{ nullptr }, 
    parent{ nullptr }, 
    priority{ p } 
{ 

    //Insert resource counters into the resource log 
    resourceLog.insert(std::pair<str, int>("R1", 0)); 
    resourceLog.insert(std::pair<str, int>("R2", 0)); 
    resourceLog.insert(std::pair<str, int>("R3", 0)); 
    resourceLog.insert(std::pair<str, int>("R4", 0)); 


    //Insert resource request counters into the request log 
    requestBackLog.insert(std::pair<str, int>("R1", 0)); 
    requestBackLog.insert(std::pair<str, int>("R2", 0)); 
    requestBackLog.insert(std::pair<str, int>("R3", 0)); 
    requestBackLog.insert(std::pair<str, int>("R4", 0)); 
} 


PCB::~PCB() 
{ 




} 

//Print the proccess ID to stdout 
void PCB::printID() 
{ 

    std::cout << pID << " "; 

} 








RCB::RCB(str name, int r) : 
    rID{ name }, 
    numResources{ r }, 
    availableResources{ r }, 
    resourcesRequested{ 0 } 
{} 


RCB::RCB(const RCB& r) 
{ 
    rID = r.rID; 
    numResources = r.numResources; 
    availableResources = r.availableResources; 
    resourcesRequested = r.resourcesRequested; 

} 

RCB::RCB() : 
    rID{ "R0" }, 
    numResources{ 5 }, 
    availableResources{ 5 }, 
    resourcesRequested{ 0 } 
{ 

} 


MainProcess::MainProcess() : 
    initProcess("init", 0), 
    currentlyRunning{ &initProcess } 

{ 

    //Add init to the list of process names 
    nameList.push_back("init"); 

    RCB R1("R1", 1); 
    RCB R2("R2", 2); 
    RCB R3("R3", 3); 
    RCB R4("R4", 4); 


    //Initialize four resources in the resource map 
    resourceMap.insert(std::pair<str, RCB>("R1", R1)); 
    resourceMap.insert(std::pair<str, RCB>("R2", R2)); 
    resourceMap.insert(std::pair<str, RCB>("R3", R3)); 
    resourceMap.insert(std::pair<str, RCB>("R4", R4)); 


    //Add a reference to the initial process to lowest list on the ready list 
    readyList[0].push_back(&initProcess); 
    initProcess.setStatus(RUNNING); 

    //Print the id of the init process to stdout 
    initProcess.printID(); 







} 

void MainProcess::Release(str rID, int num) 
{ 

    //Check for negative numbers 
    if (num < 0){ 
     std::cout << "error "; 
     return; 
    } 


    //Subtract resources from the resource log of the currently running process 
    currentlyRunning->resourceLog[rID] = std::max(currentlyRunning->resourceLog[rID] - num, 0); 

    //Add resources back to the available resources 
    resourceMap[rID].returnResources(num); 

    //Iterator pointing to the first PCB in the waitlist 
    std::list<PCB*>::iterator it = resourceMap[rID].waitList.begin(); 

    //CONDITION 
    //The waitlist on the RCB is not empty AND 
    //the amount of available resources in the RCB is greater than the amount of 
    //requested resources by the PCB at the front of the waitlist 
    while (!resourceMap[rID].waitList.empty() && resourceMap[rID].getAvailableResources() > 0 && it != resourceMap[rID].waitList.end()) 
    { 

     if ((*it)->requestBackLog[rID] <= resourceMap[rID].getAvailableResources()){ 

      //Allocate backloged resources from the RCB 
      resourceMap[rID].allocateResources((*it)->requestBackLog[rID]); 

      //Give the allocated resources to the PCB 
      (*it)->resourceLog[rID] += (*it)->requestBackLog[rID]; 

      //Zero out the request back log 
      (*it)->requestBackLog[rID] = 0; 


      //Change the status of the PCB and add it to the ready list   
      (*it)->setStatus(READY); 
      (*it)->setBackPtr(readyList); 
      readyList[(*it)->getPriority()].push_back((*it)); 

      //Move the iterator to the next element in the wait list 
      it++; 

      //Remove the PCB from the waitlist 
      resourceMap[rID].waitList.pop_front(); 


      //Call the scheduler 
      Scheduler(); 


     } 


     //If the PCB at the front of the wait list is asking for too many resources 
     //then just skip it and move on to the next PCB on the waitlist 
     else 
     { 
      it++; 
     } 



    } 



} 

void MainProcess::FreeResources(PCB* p) 
{ 

    //Free all the resources currently held by PCB p 
    for (auto& item : p->resourceLog){ 
     Release(item.first, item.second); 
    } 


} 

void MainProcess::Destroy(str PID) 
{ 

    //Search the ready list for the PCB with the specified PID 
    for (int i = 1; i < 3; i++){ 
     for (PCB* p : readyList[i]){ 
      if (p->getPID() == PID){ 
       KillTree(p); 
       Scheduler(); 
       return; 
      } 
     } 
    } 

    //If no PCB was found with PID then output error 
    std::cout << "error "; 



} 

void MainProcess::KillTree(PCB* p) 
{ 
    //Recursively call kill tree on each child 
    if (!p->children.empty()){ 
     for (PCB* child : p->children) 
     { 
      KillTree(child); 

     } 

    } 

    //If the PCB has no children then free all of its resources and delete it. 
    FreeResources(p); 
    delete p; 
    return; 


} 

void MainProcess::Create(str name, int p) 
{ 

    std::vector<str>::iterator it = std::find(nameList.begin(), nameList.end(), name); 

    if (it != nameList.end()){ 
     std::cout << "error "; 
     return; 
    } 

    else{ 

     //Add the new process name to the list of process names 
     nameList.push_back(name); 

     //Create a reference to a new process 
     PCB* newProcess = new PCB(name, p); 

     //Set the back pointer to the ready list 
     newProcess->setBackPtr(readyList); 

     //Set the parent pointer to the parent process 
     newProcess->setParent(currentlyRunning); 

     //Add it to the process tree 
     currentlyRunning->children.push_back(newProcess); 

     //Add the new process to the ready list 
     newProcess->setStatus(READY); 
     readyList[newProcess->getPriority()].push_back(newProcess); 

     //Call the scheduler 
     Scheduler(); 

    } 



} 



void MainProcess::Request(str rID, int num) 
{ 
    RCB* rcb; 

    //Check for negative numbers 
    if (num < 0){ 
     std::cout << "error "; 
     return; 
    } 

    //rcb is a reference to a resource in the resource map 
    rcb = &resourceMap[rID]; 

    //If resources are available 
    if (rcb->getAvailableResources() >= num){ 
     rcb->allocateResources(num); 

     //Give the requested resources to the running process 
     currentlyRunning->resourceLog[rID] += num; 




     //Insert RCB into resource list of currently running process if not in there already 
     std::list<RCB*>::iterator it = std::find(currentlyRunning->other_Resources.begin(), currentlyRunning->other_Resources.end(), rcb); 

     if (it == currentlyRunning->other_Resources.end()){ 

      currentlyRunning->other_Resources.push_back(rcb); 

     } 
    } 



    else 
    { 

     //Stop the process from running and put it on the blocked list 
     currentlyRunning->setStatus(BLOCKED); 
     currentlyRunning->setBackPtr(&rcb->waitList); 

     readyList[currentlyRunning->getPriority()].pop_front(); 
     rcb->waitList.push_back(currentlyRunning); 

     //Log the requested amount in the request back log 
     currentlyRunning->requestBackLog[rID] += num; 

     //Call Scheduler 
     Scheduler(); 


    } 

} 


void MainProcess::Scheduler() 
{ 

    PCB* p = getHighestPriority(); 

    if (currentlyRunning != p){ 

     //Set the currently running process to the 
     currentlyRunning = p; 

     //Set the status of the currently running process to "RUNNING" 
     currentlyRunning->setStatus(RUNNING); 
    } 

    //Print the id of the currently running process 
    currentlyRunning->printID(); 

} 

void MainProcess::TimeOut() 
{ 


    //Remove currently running process from the front of the list and put it in the back 
    readyList[currentlyRunning->getPriority()].pop_front(); 
    currentlyRunning->setStatus(READY); 
    readyList[currentlyRunning->getPriority()].push_back(currentlyRunning); 

    Scheduler(); 

} 

PCB* MainProcess::getHighestPriority() 
{ 
    //Iterate through the ready list to find the highest priority process 
    for (int i = 2; i >= 0; i--){ 
     if (!readyList[i].empty()){ 
      return readyList[i].front(); 
     } 
    } 

    //Return null if no process is found 
    return nullptr; 
} 

void MainProcess::Reset() 
{ 

    for (PCB* p : initProcess.children){ 

     KillTree(p); 

    } 

    Scheduler(); 


} 

Я довольно уверен, что это где проблема

//Add init to the list of process names 
    nameList.push_back("init"); 

    RCB R1("R1", 1); 
    RCB R2("R2", 2); 
    RCB R3("R3", 3); 
    RCB R4("R4", 4); 


    //Initialize four resources in the resource map 
    resourceMap.insert(std::pair<str, RCB>("R1", R1)); 
    resourceMap.insert(std::pair<str, RCB>("R2", R2)); 
    resourceMap.insert(std::pair<str, RCB>("R3", R3)); 
    resourceMap.insert(std::pair<str, RCB>("R4", R4)); 

Answer 1

При определении параметризованного конструктора [RCB (имя, ул ИНТ г)] , компилятор НЕ будет генерировать конструктор аргументов по умолчанию no arguments. Поэтому в вашем случае, если вы попытаетесь создать объект RCB [RCB obj;], он обязательно должен будет выбросить эту ошибку. Чтобы решить проблему, вам нужно определить конструктор args по умолчанию. Не уверен, что это поможет.

Answer 2

Согласно ошибке, класс RCB не имеет конструктора по умолчанию. Это отлично. Не все классы должны иметь конструктор по умолчанию. Однако что-то из вашего кода, использующего RCB (не часть того, что вы включили в вопрос), пытается вызвать конструктор по умолчанию RCB, явно или неявно.

Например, если вы объявляете где-то в коде

RCB rcb; 

Затем вы используете конструктор по умолчанию.