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  • Disturbing or politically incorrect classes

    - by Jonas B
    Please don't take this seriously! - Community wikied Satire is always fun. Try to come up with the most shocking, disturbing or politically incorrect class you can think of. (But please no racism or anything seriously offensive or anything that can't be interpeted as satire). I'll go first with my example: public class Person { public bool Female; public Person(bool female) { Female = female; } public static bool operator <(Person j1, Person j2) { if (j1.Female && !j2.Female) return true; else return false; } public static bool operator >(Person j1, Person j2) { if (!j1.Female && j2.Female) return true; else return false; } public static bool operator <=(Person j1, Person j2) { if ((j1.Female == j2.Female) || (j1.Female && !j2.Female)) return true; else return false; } public static bool operator >=(Person j1, Person j2) { if ((j1.Female == j2.Female) || (!j1.Female && j2.Female)) return true; else return false; } }

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  • Win32 DLL importing issues (DllMain)

    - by brady
    I have a native DLL that is a plug-in to a different application (one that I have essentially zero control of). Everything works just great until I link with an additional .lib file (links my DLL to another DLL named ABQSMABasCoreUtils.dll). This file contains some additional API from the parent application that I would like to utilize. I haven't even written any code to use any of the functions exported but just linking in this new DLL is causing problems. Specifically I get the following error when I attempt to run the program: The application failed to initialize properly (0xc0000025). Clock on OK to terminate the application. I believe I have read somewhere that this is typically due to a DllMain function returning FALSE. Also, the following message is written to the standard output: ERROR: Memory allocation attempted before component initialization I am almost 100% sure this error message is coming from the application and is not some type of Windows error. Looking into this a little more (aka flailing around and flipping every switch I know of) I linked with /MAP turned on and found this in the resulting .map file: 0001:000af220 ??3@YAXPEAX@Z 00000001800b0220 f ABQSMABasCoreUtils_import:ABQSMABasCoreUtils.dll 0001:000af226 ??2@YAPEAX_K@Z 00000001800b0226 f ABQSMABasCoreUtils_import:ABQSMABasCoreUtils.dll 0001:000af22c ??_U@YAPEAX_K@Z 00000001800b022c f ABQSMABasCoreUtils_import:ABQSMABasCoreUtils.dll 0001:000af232 ??_V@YAXPEAX@Z 00000001800b0232 f ABQSMABasCoreUtils_import:ABQSMABasCoreUtils.dll If I undecorate those names using "undname" they give the following (same order): void __cdecl operator delete(void * __ptr64) void * __ptr64 __cdecl operator new(unsigned __int64) void * __ptr64 __cdecl operator new[](unsigned __int64) void __cdecl operator delete[](void * __ptr64) I am not sure I understand how anything from ABQSMABasCoreUtils.dll can exist within this .map file or why my DLL is even attempting to load ABQSMABasCoreUtils.dll if I don't have any code that references this DLL. Can anyone help me put this information together and find out why this isn't working? For what it's worth I have confirmed via "dumpbin" that the parent application imports the same DLL (ABQSMABasCoreUtils.dll), so it is being loaded no matter what. I have also tried delay loading this DLL in my DLL but that did not change the results.

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  • operators computing direction

    - by amiad
    Hi all! I enqunterd something that I can't understand. I have this code: cout << "f1 * f1 + f2 * f1 - f1 / f2 is: "<< f1 * f1 + f2 * f1 - f1 / f2 << endl; All the "f"s are objects, and all the operators are overloaded. The weird this is that the first computarion is of the "/" operator, then the second "" and then the first "", after that - the operator "+" and at last - operator "-". So basicly - the "/" and "*" worked from right to left, and the "+" and "-" operators worked from left to right. I made another test... I checked this code: cout << "f1 * f1 / f2 is: " << f1 * f1 / f2 << endl; Now, the first operator was "*" and only then oerator "/". So now, it worked from left to right. Can someone help me underatand why is there diffrence in the directions? 10X!

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  • How do I improve my performance with this singly linked list struct within my program?

    - by Jesus
    Hey guys, I have a program that does operations of sets of strings. We have to implement functions such as addition and subtraction of two sets of strings. We are suppose to get it down to the point where performance if of O(N+M), where N,M are sets of strings. Right now, I believe my performance is at O(N*M), since I for each element of N, I go through every element of M. I'm particularly focused on getting the subtraction to the proper performance, as if I can get that down to proper performance, I believe I can carry that knowledge over to the rest of things I have to implement. The '-' operator is suppose to work like this, for example. Declare set1 to be an empty set. Declare set2 to be a set with { a b c } elements Declare set3 to be a set with ( b c d } elements set1 = set2 - set3 And now set1 is suppose to equal { a }. So basically, just remove any element from set3, that is also in set2. For the addition implementation (overloaded '+' operator), I also do the sorting of the strings (since we have to). All the functions work right now btw. So I was wondering if anyone could a) Confirm that currently I'm doing O(N*M) performance b) Give me some ideas/implementations on how to improve the performance to O(N+M) Note: I cannot add any member variables or functions to the class strSet or to the node structure. The implementation of the main program isn't very important, but I will post the code for my class definition and the implementation of the member functions: strSet2.h (Implementation of my class and struct) // Class to implement sets of strings // Implements operators for union, intersection, subtraction, // etc. for sets of strings // V1.1 15 Feb 2011 Added guard (#ifndef), deleted using namespace RCH #ifndef _STRSET_ #define _STRSET_ #include <iostream> #include <vector> #include <string> // Deleted: using namespace std; 15 Feb 2011 RCH struct node { std::string s1; node * next; }; class strSet { private: node * first; public: strSet (); // Create empty set strSet (std::string s); // Create singleton set strSet (const strSet &copy); // Copy constructor ~strSet (); // Destructor int SIZE() const; bool isMember (std::string s) const; strSet operator + (const strSet& rtSide); // Union strSet operator - (const strSet& rtSide); // Set subtraction strSet& operator = (const strSet& rtSide); // Assignment }; // End of strSet class #endif // _STRSET_ strSet2.cpp (implementation of member functions) #include <iostream> #include <vector> #include <string> #include "strset2.h" using namespace std; strSet::strSet() { first = NULL; } strSet::strSet(string s) { node *temp; temp = new node; temp->s1 = s; temp->next = NULL; first = temp; } strSet::strSet(const strSet& copy) { if(copy.first == NULL) { first = NULL; } else { node *n = copy.first; node *prev = NULL; while (n) { node *newNode = new node; newNode->s1 = n->s1; newNode->next = NULL; if (prev) { prev->next = newNode; } else { first = newNode; } prev = newNode; n = n->next; } } } strSet::~strSet() { if(first != NULL) { while(first->next != NULL) { node *nextNode = first->next; first->next = nextNode->next; delete nextNode; } } } int strSet::SIZE() const { int size = 0; node *temp = first; while(temp!=NULL) { size++; temp=temp->next; } return size; } bool strSet::isMember(string s) const { node *temp = first; while(temp != NULL) { if(temp->s1 == s) { return true; } temp = temp->next; } return false; } strSet strSet::operator + (const strSet& rtSide) { strSet newSet; newSet = *this; node *temp = rtSide.first; while(temp != NULL) { string newEle = temp->s1; if(!isMember(newEle)) { if(newSet.first==NULL) { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = NULL; newSet.first = newNode; } else if(newSet.SIZE() == 1) { if(newEle < newSet.first->s1) { node *tempNext = newSet.first; node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = tempNext; newSet.first = newNode; } else { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = NULL; newSet.first->next = newNode; } } else { node *prev = NULL; node *curr = newSet.first; while(curr != NULL) { if(newEle < curr->s1) { if(prev == NULL) { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = curr; newSet.first = newNode; break; } else { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = curr; prev->next = newNode; break; } } if(curr->next == NULL) { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = NULL; curr->next = newNode; break; } prev = curr; curr = curr->next; } } } temp = temp->next; } return newSet; } strSet strSet::operator - (const strSet& rtSide) { strSet newSet; newSet = *this; node *temp = rtSide.first; while(temp != NULL) { string element = temp->s1; node *prev = NULL; node *curr = newSet.first; while(curr != NULL) { if( element < curr->s1 ) break; if( curr->s1 == element ) { if( prev == NULL) { node *duplicate = curr; newSet.first = newSet.first->next; delete duplicate; break; } else { node *duplicate = curr; prev->next = curr->next; delete duplicate; break; } } prev = curr; curr = curr->next; } temp = temp->next; } return newSet; } strSet& strSet::operator = (const strSet& rtSide) { if(this != &rtSide) { if(first != NULL) { while(first->next != NULL) { node *nextNode = first->next; first->next = nextNode->next; delete nextNode; } } if(rtSide.first == NULL) { first = NULL; } else { node *n = rtSide.first; node *prev = NULL; while (n) { node *newNode = new node; newNode->s1 = n->s1; newNode->next = NULL; if (prev) { prev->next = newNode; } else { first = newNode; } prev = newNode; n = n->next; } } } return *this; }

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  • c++ queue template

    - by Dalton Conley
    ALright, pardon my messy code please. Below is my queue class. #include <iostream> using namespace std; #ifndef QUEUE #define QUEUE /*---------------------------------------------------------------------------- Student Class # Methods # Student() // default constructor Student(string, int) // constructor display() // out puts a student # Data Members # Name // string name Id // int id ----------------------------------------------------------------------------*/ class Student { public: Student() { } Student(string iname, int iid) { name = iname; id = iid; } void display(ostream &out) const { out << "Student Name: " << name << "\tStudent Id: " << id << "\tAddress: " << this << endl; } private: string name; int id; }; // define a typedef of a pointer to a student. typedef Student * StudentPointer; template <typename T> class Queue { public: /*------------------------------------------------------------------------ Queue Default Constructor Preconditions: none Postconditions: assigns default values for front and back to 0 description: constructs a default empty Queue. ------------------------------------------------------------------------*/ Queue() : myFront(0), myBack(0) {} /*------------------------------------------------------------------------ Copy Constructor Preconditions: requres a reference to a value for which you are copying Postconditions: assigns a copy to the parent Queue. description: Copys a queue and assigns it to the parent Queue. ------------------------------------------------------------------------*/ Queue(const T & q) { myFront = myBack = 0; if(!q.empty()) { // copy the first node myFront = myBack = new Node(q.front()); NodePointer qPtr = q.myFront->next; while(qPtr != NULL) { myBack->next = new Node(qPtr->data); myBack = myBack->next; qPtr = qPtr->next; } } } /*------------------------------------------------------------------------ Destructor Preconditions: none Postconditions: deallocates the dynamic memory for the Queue description: deletes the memory stored for a Queue. ------------------------------------------------------------------------*/ ~Queue() { NodePointer prev = myFront, ptr; while(prev != NULL) { ptr = prev->next; delete prev; prev = ptr; } } /*------------------------------------------------------------------------ Empty() Preconditions: none Postconditions: returns a boolean value. description: returns true/false based on if the queue is empty or full. ------------------------------------------------------------------------*/ bool empty() const { return (myFront == NULL); } /*------------------------------------------------------------------------ Enqueue Preconditions: requires a constant reference Postconditions: allocates memory and appends a value at the end of a queue description: ------------------------------------------------------------------------*/ void enqueue(const T & value) { NodePointer newNodePtr = new Node(value); if(empty()) { myFront = myBack = newNodePtr; newNodePtr->next = NULL; } else { myBack->next = newNodePtr; myBack = newNodePtr; newNodePtr->next = NULL; } } /*------------------------------------------------------------------------ Display Preconditions: requires a reference of type ostream Postconditions: returns the ostream value (for chaining) description: outputs the contents of a queue. ------------------------------------------------------------------------*/ void display(ostream & out) const { NodePointer ptr; ptr = myFront; while(ptr != NULL) { out << ptr->data << " "; ptr = ptr->next; } out << endl; } /*------------------------------------------------------------------------ Front Preconditions: none Postconditions: returns a value of type T description: returns the first value in the parent Queue. ------------------------------------------------------------------------*/ T front() const { if ( !empty() ) return (myFront->data); else { cerr << "*** Queue is empty -- returning garbage value ***\n"; T * temp = new(T); T garbage = * temp; delete temp; return garbage; } } /*------------------------------------------------------------------------ Dequeue Preconditions: none Postconditions: removes the first value in a queue ------------------------------------------------------------------------*/ void dequeue() { if ( !empty() ) { NodePointer ptr = myFront; myFront = myFront->next; delete ptr; if(myFront == NULL) myBack = NULL; } else { cerr << "*** Queue is empty -- " "can't remove a value ***\n"; exit(1); } } /*------------------------------------------------------------------------ pverloaded = operator Preconditions: requires a constant reference Postconditions: returns a const type T description: this allows assigning of queues to queues ------------------------------------------------------------------------*/ Queue<T> & operator=(const T &q) { // make sure we arent reassigning ourself // e.g. thisQueue = thisQueue. if(this != &q) { this->~Queue(); if(q.empty()) { myFront = myBack = NULL; } else { myFront = myBack = new Node(q.front()); NodePointer qPtr = q.myFront->next; while(qPtr != NULL) { myBack->next = new Node(qPtr->data); myBack = myBack->next; qPtr = qPtr->next; } } } return *this; } private: class Node { public: T data; Node * next; Node(T value, Node * first = 0) : data(value), next(first) {} }; typedef Node * NodePointer; NodePointer myFront, myBack, queueSize; }; /*------------------------------------------------------------------------ join Preconditions: requires 2 queue values Postconditions: appends queue2 to the end of queue1 description: this function joins 2 queues into 1. ------------------------------------------------------------------------*/ template <typename T> Queue<T> join(Queue<T> q1, Queue<T> q2) { Queue<T> q1Copy(q1), q2Copy(q2); Queue<T> jQueue; while(!q1Copy.empty()) { jQueue.enqueue(q1Copy.front()); q1Copy.dequeue(); } while(!q2Copy.empty()) { jQueue.enqueue(q2Copy.front()); q2Copy.dequeue(); } cout << jQueue << endl; return jQueue; } /*---------------------------------------------------------------------------- Overloaded << operator Preconditions: requires a constant reference and a Queue of type T Postconditions: returns the ostream (for chaining) description: this function is overloaded for outputing a queue with << ----------------------------------------------------------------------------*/ template <typename T> ostream & operator<<(ostream &out, Queue<T> &s) { s.display(out); return out; } /*---------------------------------------------------------------------------- Overloaded << operator Preconditions: requires a constant reference and a reference of type Student Postconditions: none description: this function is overloaded for outputing an object of type Student. ----------------------------------------------------------------------------*/ ostream & operator<<(ostream &out, Student &s) { s.display(out); } /*---------------------------------------------------------------------------- Overloaded << operator Preconditions: requires a constant reference and a reference of a pointer to a Student object. Postconditions: none description: this function is overloaded for outputing pointers to Students ----------------------------------------------------------------------------*/ ostream & operator<<(ostream &out, StudentPointer &s) { s->display(out); } #endif Now I'm having some issues with it. For one, when I add 0 to a queue and then I output the queue like so.. Queue<double> qdub; qdub.enqueue(0); cout << qdub << endl; That works, it will output 0. But for example, if I modify that queue in any way.. like.. assign it to a different queue.. Queue<double> qdub1; Queue<double> qdub2; qdub1.enqueue(0; qdub2 = qdub1; cout << qdub2 << endl; It will give me weird values for 0 like.. 7.86914e-316. Help on this would be much appreciated!

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  • Division by zero: Undefined Behavior or Implementation Defined in C and/or C++ ?

    - by SiegeX
    Regarding division by zero, the standards say: C99 6.5.5p5 - The result of the / operator is the quotient from the division of the first operand by the second; the result of the % operator is the remainder. In both operations, if the value of the second operand is zero, the behavior is undefined. C++03 5.6.4 - The binary / operator yields the quotient, and the binary % operator yields the remainder from the division of the first expression by the second. If the second operand of / or % is zero the behavior is undefined. If we were to take the above paragraphs at face value, the answer is clearly Undefined Behavior for both languages. However, if we look further down in the C99 standard we see the following paragraph which appears to be contradictory(1): C99 7.12p4 - The macro INFINITY expands to a constant expression of type float representing positive or unsigned infinity, if available; Do the standards have some sort of golden rule where Undefined Behavior cannot be superseded by a (potentially) contradictory statement? Barring that, I don't think it's unreasonable to conclude that if your implementation defines the INFINITY macro, division by zero is defined to be such. However, if your implementation does not define such a macro, the behavior is Undefined. I'm curious what the consensus on this matter for each of the two languages. Would the answer change if we are talking about integer division int i = 1 / 0 versus floating point division float i = 1.0 / 0.0 ? Note (1) The C++03 standard talks about the library which includes the INFINITY macro.

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  • multiple definition in header file

    - by Jérôme
    Here is a small code-example from which I'd like to ask a question : complex.h : #ifndef COMPLEX_H #define COMPLEX_H #include <iostream> class Complex { public: Complex(float Real, float Imaginary); float real() const { return m_Real; }; private: friend std::ostream& operator<<(std::ostream& o, const Complex& Cplx); float m_Real; float m_Imaginary; }; std::ostream& operator<<(std::ostream& o, const Complex& Cplx) { return o << Cplx.m_Real << " i" << Cplx.m_Imaginary; } #endif // COMPLEX_H complex.cpp : #include "complex.h" Complex::Complex(float Real, float Imaginary) { m_Real = Real; m_Imaginary = Imaginary; } main.cpp : #include "complex.h" #include <iostream> int main() { Complex Foo(3.4, 4.5); std::cout << Foo << "\n"; return 0; } When compiling this code, I get the following error : multiple definition of operator<<(std::ostream&, Complex const&) I've found that making this fonction inline solves the problem, but I don't understand why. Why does the compiler complain about multiple definition ? My header file is guarded (with #define COMPLEX_H). And, if complaining about the operator<< fonction, why not complain about the public real() fonction, which is defined in the header as well ? And is there another solution as using the inline keyword ?

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  • The correct usage of nested #pragma omp for directives

    - by GoldenLee
    The following code runs like a charm before OpenMP parallelization was applied. In fact, the following code was in a state of endless loop! I'm sure that's result from my incorrect use to the OpenMP directives. Would you please show me the correct way? Thank you very much. #pragma omp parallel for for (int nY = nYTop; nY <= nYBottom; nY++) { for (int nX = nXLeft; nX <= nXRight; nX++) { // Use look-up table for performance dLon = theApp.m_LonLatLUT.LonGrid()[nY][nX] + m_FavoriteSVISSRParams.m_dNadirLon; dLat = theApp.m_LonLatLUT.LatGrid()[nY][nX]; // If you don't want to use longitude/latitude look-up table, uncomment the following line //NOMGeoLocate.XYToGEO(dLon, dLat, nX, nY); if (dLon > 180 || dLat > 180) { continue; } if (Navigation.GeoToXY(dX, dY, dLon, dLat, 0) > 0) { continue; } // Skip void data scanline dY = dY - nScanlineOffset; // Compute coefficients as well as its four neighboring points' values nX1 = int(dX); nX2 = nX1 + 1; nY1 = int(dY); nY2 = nY1 + 1; dCx = dX - nX1; dCy = dY - nY1; dP1 = pIRChannelData->operator [](nY1)[nX1]; dP2 = pIRChannelData->operator [](nY1)[nX2]; dP3 = pIRChannelData->operator [](nY2)[nX1]; dP4 = pIRChannelData->operator [](nY2)[nX2]; // Bilinear interpolation usNomDataBlock[nY][nX] = (unsigned short)BilinearInterpolation(dCx, dCy, dP1, dP2, dP3, dP4); } }

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  • Getting a type for a template instantiation?

    - by ebo
    I have the following situation: I have a object of type MyClass, which has a method to cast itself to it's base class. The class includes a typedef for it's base class and a method to do the downcast. template <class T, class B> class BaseClass; template <class T> class NoAccess; template <class T> class MyClass : public BaseClass<T, NoAccess<T> > { private: typedef BaseClass<T, NoAccess<T> > base; public: base &to_base(); }; I need to pass the result of a base call to a functor Operator: template <class Y> class Operator { Operator(Y &x); }; Operator<???> op(myobject.to_base()); Is there a easy way to fill the ??? provided that I do not want to use NoAccess?

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  • Syntax for finding structs in multisets - C++

    - by Sarah
    I can't seem to figure out the syntax for finding structs in containers. I have a multiset of Event structs. I'm trying to find one of these structs by searching on its key. I get the compiler error commented below. struct Event { public: bool operator < ( const Event & rhs ) const { return ( time < rhs.time ); } bool operator > ( const Event & rhs ) const { return ( time > rhs.time ); } bool operator == ( const Event & rhs ) const { return ( time == rhs.time ); } double time; int eventID; int hostID; int s; }; typedef std::multiset< Event, std::less< Event > > EventPQ; EventPQ currentEvents; double oldRecTime = 20.0; EventPQ::iterator ceItr = currentEvents.find( EventPQ::key_type( oldRecTime ) ); // no matching function call I've tried a few permutations to no avail. I thought defining the conditional equality operator was going to be enough.

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  • C++ Problem: Class Promotion using derived class

    - by Michael Fitzpatrick
    I have a class for Float32 that is derived from Float32_base class Float32_base { public: // Constructors Float32_base(float x) : value(x) {}; Float32_base(void) : value(0) {}; operator float32(void) {return value;}; Float32_base operator =(float x) {value = x; return *this;}; Float32_base operator +(float x) const { return value + x;}; protected: float value; } class Float32 : public Float32_base { public: float Tad() { return value + .01; } } int main() { Float32 x, y, z; x = 1; y = 2; // WILL NOT COMPILE! z = (x + y).Tad(); // COMPILES OK z = ((Float32)(x + y)).Tad(); } The issue is that the + operator returns a Float32_base and Tad() is not in that class. But 'x' and 'y' are Float32's. Is there a way that I can get the code in the first line to compile without having to resort to a typecast like I did on the next line?

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  • Can't figure out where race condition is occuring

    - by Nik
    I'm using Valgrind --tool=drd to check my application that uses Boost::thread. Basically, the application populates a set of "Book" values with "Kehai" values based on inputs through a socket connection. On a seperate thread, a user can connect and get the books send to them. Its fairly simple, so i figured using a boost::mutex::scoped_lock on the location that serializes the book and the location that clears out the book data should be suffice to prevent any race conditions. Here is the code: void Book::clear() { boost::mutex::scoped_lock lock(dataMutex); for(int i =NUM_KEHAI-1; i >= 0; --i) { bid[i].clear(); ask[i].clear(); } } int Book::copyChangedKehaiToString(char* dst) const { boost::mutex::scoped_lock lock(dataMutex); sprintf(dst, "%-4s%-13s",market.c_str(),meigara.c_str()); int loc = 17; for(int i = 0; i < Book::NUM_KEHAI; ++i) { if(ask[i].changed > 0) { sprintf(dst+loc,"A%i%-21s%-21s%-21s%-8s%-4s",i,ask[i].price.c_str(),ask[i].volume.c_str(),ask[i].number.c_str(),ask[i].postTime.c_str(),ask[i].status.c_str()); loc += 77; } } for(int i = 0; i < Book::NUM_KEHAI; ++i) { if(bid[i].changed > 0) { sprintf(dst+loc,"B%i%-21s%-21s%-21s%-8s%-4s",i,bid[i].price.c_str(),bid[i].volume.c_str(),bid[i].number.c_str(),bid[i].postTime.c_str(),bid[i].status.c_str()); loc += 77; } } return loc; } The clear() function and the copyChangedKehaiToString() function are called in the datagetting thread and data sending thread,respectively. Also, as a note, the class Book: struct Book { private: Book(const Book&); Book& operator=(const Book&); public: static const int NUM_KEHAI=10; struct Kehai; friend struct Book::Kehai; struct Kehai { private: Kehai& operator=(const Kehai&); public: std::string price; std::string volume; std::string number; std::string postTime; std::string status; int changed; Kehai(); void copyFrom(const Kehai& other); Kehai(const Kehai& other); inline void clear() { price.assign(""); volume.assign(""); number.assign(""); postTime.assign(""); status.assign(""); changed = -1; } }; std::vector<Kehai> bid; std::vector<Kehai> ask; tm recTime; mutable boost::mutex dataMutex; Book(); void clear(); int copyChangedKehaiToString(char * dst) const; }; When using valgrind --tool=drd, i get race condition errors such as the one below: ==26330== Conflicting store by thread 1 at 0x0658fbb0 size 4 ==26330== at 0x653AE68: std::string::_M_mutate(unsigned int, unsigned int, unsigned int) (in /usr/lib/libstdc++.so.6.0.8) ==26330== by 0x653AFC9: std::string::_M_replace_safe(unsigned int, unsigned int, char const*, unsigned int) (in /usr/lib/libstdc++.so.6.0.8) ==26330== by 0x653B064: std::string::assign(char const*, unsigned int) (in /usr/lib/libstdc++.so.6.0.8) ==26330== by 0x653B134: std::string::assign(char const*) (in /usr/lib/libstdc++.so.6.0.8) ==26330== by 0x8055D64: Book::Kehai::clear() (Book.h:50) ==26330== by 0x8094A29: Book::clear() (Book.cpp:78) ==26330== by 0x808537E: RealKernel::start() (RealKernel.cpp:86) ==26330== by 0x804D15A: main (main.cpp:164) ==26330== Allocation context: BSS section of /usr/lib/libstdc++.so.6.0.8 ==26330== Other segment start (thread 2) ==26330== at 0x400BB59: pthread_mutex_unlock (drd_pthread_intercepts.c:633) ==26330== by 0xC59565: pthread_mutex_unlock (in /lib/libc-2.5.so) ==26330== by 0x805477C: boost::mutex::unlock() (mutex.hpp:56) ==26330== by 0x80547C9: boost::unique_lock<boost::mutex>::~unique_lock() (locks.hpp:340) ==26330== by 0x80949BA: Book::copyChangedKehaiToString(char*) const (Book.cpp:134) ==26330== by 0x80937EE: BookSerializer::serializeBook(Book const&, std::string const&) (BookSerializer.cpp:41) ==26330== by 0x8092D05: BookSnapshotManager::getSnaphotDataList() (BookSnapshotManager.cpp:72) ==26330== by 0x8088179: SnapshotServer::getDataList() (SnapshotServer.cpp:246) ==26330== by 0x808870F: SnapshotServer::run() (SnapshotServer.cpp:183) ==26330== by 0x808BAF5: boost::_mfi::mf0<void, RealThread>::operator()(RealThread*) const (mem_fn_template.hpp:49) ==26330== by 0x808BB4D: void boost::_bi::list1<boost::_bi::value<RealThread*> >::operator()<boost::_mfi::mf0<void, RealThread>, boost::_bi::list0>(boost::_bi::type<void>, boost::_mfi::mf0<void, RealThread>&, boost::_bi::list0&, int) (bind.hpp:253) ==26330== by 0x808BB90: boost::_bi::bind_t<void, boost::_mfi::mf0<void, RealThread>, boost::_bi::list1<boost::_bi::value<RealThread*> > >::operator()() (bind_template.hpp:20) ==26330== Other segment end (thread 2) ==26330== at 0x400B62A: pthread_mutex_lock (drd_pthread_intercepts.c:580) ==26330== by 0xC59535: pthread_mutex_lock (in /lib/libc-2.5.so) ==26330== by 0x80546B8: boost::mutex::lock() (mutex.hpp:51) ==26330== by 0x805473B: boost::unique_lock<boost::mutex>::lock() (locks.hpp:349) ==26330== by 0x8054769: boost::unique_lock<boost::mutex>::unique_lock(boost::mutex&) (locks.hpp:227) ==26330== by 0x8094711: Book::copyChangedKehaiToString(char*) const (Book.cpp:113) ==26330== by 0x80937EE: BookSerializer::serializeBook(Book const&, std::string const&) (BookSerializer.cpp:41) ==26330== by 0x808870F: SnapshotServer::run() (SnapshotServer.cpp:183) ==26330== by 0x808BAF5: boost::_mfi::mf0<void, RealThread>::operator()(RealThread*) const (mem_fn_template.hpp:49) ==26330== by 0x808BB4D: void boost::_bi::list1<boost::_bi::value<RealThread*> >::operator()<boost::_mfi::mf0<void, RealThread>, boost::_bi::list0>(boost::_bi::type<void>, boost::_mfi::mf0<void, RealThread>&, boost::_bi::list0&, int) (bind.hpp:253) For the life of me, i can't figure out where the race condition is. As far as I can tell, clearing the kehai is done only after having taken the mutex, and the same holds true with copying it to a string. Does anyone have any ideas what could be causing this, or where I should look? Thank you kindly.

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  • Having an issue with overwriting an element of a file correctly (numeric)

    - by IngeniousHax
    This is an ATM style program, but currently it doesn't do exactly what I need it to do... I need to get the current balance, and when money is transferred from either checking or savings, it should add it to checking and subtract it from savings. which is does, but not correctly... Input example -=[ Funds Transfer ]=- -=[ Savings to Checking ]=- Account Name: nomadic Amount to transfer: $400 New Balance in Checking: $900 // original was 500 New Balance in Savings: $7.7068e+012 // this should now be 1100... Here is my code, it's a lot of code, but there are no errors, so throwing it into an IDE and compiling should be fairly quick for whoever would like to help. mainBankClass.h mainBankClass.h #ifndef MAINBANKCLASS_H #define MAINBANKCLASS_H #include <iostream> #include <fstream> #include <string> using namespace std; class Banking { protected: string checkAcctName, saveAcctName; // Name on the account int acctNumber[13]; // Account number float acctBalance, initSaveDeposit, initCheckDeposit, depAmt; // amount in account, and amount to deposit public: char getBalanceChoice(); // Get name on account for displaying relevant information char newAccountMenu(); // Create a new account and assign it a random account number void invalid(char *); // If an invalid option is chosen char menu(); // Print the main menu for the user. virtual float deposit(){ return 0; } // virtual function for deposits // virtual float withdrawal() = 0; // Virtual function for withdrawals void fatal(char *); // Handles fatal errors. Banking(); }; class Checking : public Banking { public: friend ostream operator<<(ostream &, Checking &); friend istream operator>>(istream &, Checking &); Checking operator <= (const Checking &) const; void newCheckingAccount(); void viewCheckingBalance(); void transferFromSaving(); float deposit() { return (acctBalance += depAmt); } }; class Saving : public Banking { public: friend ostream &operator<<(ostream &, Saving &); friend istream &operator>>(istream &, Saving &); Saving operator <= (const Saving &) const; void newSavingAccount(); void viewSavingBalance(); void transferFromChecking(); float deposit() { return (acctBalance += depAmt); } }; class checkAndSave : public Banking { public: void newCheckAndSave(); void viewBothBalances(); }; #endif bankAccount.cpp #include <iostream> #include <sstream> #include <string> #include <iomanip> #include <fstream> #include <time.h> #include "MainBankClass.h" /*****************************\ | BANKING CONSTRUCTOR | \*****************************/ Banking::Banking() { string acctName; // Name on the account acctNumber[13] = 0; // Account number acctBalance = 0; initCheckDeposit = 0; initSaveDeposit = 0; depAmt = 0; }; /********************************\ | The following code is to print the menu | | and recieve the users choice on what | | they want to do with the ATM | \********************************/ char Banking::menu() { char choice; system("cls"); cout << "\t\t -=[ Main Menu ]=- \n\n" << "\tA) Create New Account\n" << "\tB) View Account Balance\n" << "\tC) Transfer Funds From Checking To Savings\n" << "\tD) Transfer Funds From Savings To Checking\n" << "\tE) Exit\n" << "\n\n\tSelection: "; cin >> choice; cin.ignore(); choice = toupper(choice); while(!isalpha(choice)) { invalid("[!!] Invalid selection.\n[!!] Choose a valid option: "); cin >> choice; cin.ignore(); } return choice; } /*********************\ | Will read in account choic | | and display it for the user | \*********************/ char Banking::getBalanceChoice() { char choice; fstream saveFile("saving.dat", ios::in | ios::beg); system("cls"); cout << "\t\t -=[ View Account Balance ]=-\n\n"; cout << "A) View Checking Account\n" << "B) View Saving Account\n" << "C) View Checking \\ Saving Account\n" << endl; cout << "Choice: "; cin >> choice; choice = toupper(choice); if(!isalpha(choice)) fatal(" [!!] Invalid Choice"); return choice; } /***************************\ | Incase an invalid decision to made | | this throws the error message sent | | to it by the calling area | \***************************/ void Banking::invalid(char *msg) { cout << msg; } /*************************\ | Used if files can not be opened | | and exits with code 251: | | miscommunication with server | \*************************/ void Banking::fatal(char *msg) { cout << msg; exit(1); } /***************************\ | Create an account, either checking | | or savings, or both. | | Must should create a randomly | | generated account number that will | | correspond with each account. | \***************************/ /************************\ NOTE:: WILL BE UPDATED TO CONTAIN A PIN FOR ACCOUNT VERIFICATION *************************/ char Banking::newAccountMenu() { srand(time(NULL)); // Seed random generator with time initialized to NULL char acctChoice; // choice for the account type ofstream checkFile("checking.dat", ios::out | ios::app); // For saving checking accounts ofstream saveFile("saving.dat", ios::out | ios::app); // For saving savings accounts system("cls"); cout << "\t\t-=[ New Account Creation ]=-\n\n" << endl; cout << "A) Checking Account\n" << "B) Savings Account\n" << "C) Checking and Saving Account\n" << endl; cout << "New account type: "; cin >> acctChoice; acctChoice = toupper(acctChoice); cin.clear(); cin.sync(); return acctChoice; } /********************************************************************* ********************************************************************** CHECKING ACCOUNT CODE ********************************************************************** **********************************************************************/ // New Checking Account Creation void Checking::newCheckingAccount() { system("cls"); ofstream checkFile("checking.dat", ios::out | ios::app); // For saving checking accounts cout << "\t\t -=[ New Checking Account ]=- \n" << endl; cout << "Name of the main holder to be on the account: "; getline(cin, checkAcctName); cout << "Initial deposit amount: $"; cin >> initCheckDeposit; if(initCheckDeposit <= 0) { while(initCheckDeposit <= 0) { invalid("[!!] 0 or negative amount entered\nMaybe a typo?\n"); cout << "Deposit Amount: $"; cin >> initCheckDeposit; } } if(!checkFile) fatal("[!!] Fatal Error 251: Miscommunication with server\n"); checkFile << checkAcctName << endl; for(int j = 0; j < 13; j++) { acctNumber[j] = (rand() % 10); // Build a random checking account number checkFile << acctNumber[j]; } checkFile << endl; checkFile << initCheckDeposit << endl; checkFile.close(); } void Checking::viewCheckingBalance() { fstream checkFile("checking.dat", ios::in | ios::beg); string name; int i = 0; double balance = 0; system("cls"); cout << "\t\t -=[ View Checking Account ]=-\n\n" << endl; cout << "Account Name: "; cin.sync(); getline(cin, name); getline(checkFile, checkAcctName); while(name != checkAcctName && !checkFile.fail()) { i++; getline(checkFile, checkAcctName); } if(name == checkAcctName) { system("cls"); cout << "\t\t -=[ Checking Account Balance ]=-\n\n" << endl; cout << "Account Name: " << checkAcctName << "\n"; cout << "Account Number: "; for(int j = 0; j < 13; j++) { char input_number; stringstream converter; checkFile.get(input_number); converter << input_number; converter >> acctNumber[j]; cout << acctNumber[j]; } // if balance a problem, try the below commented out line // checkFile.ignore(numeric_limits<streamsize>::max(), '\n'); cout << endl; checkFile >> acctBalance; cout << "Balance: $" << fixed << showpoint << setprecision(2) << acctBalance << endl; } else fatal("[!!] Invalid Account\n"); checkFile.close(); getchar(); } void Checking::transferFromSaving() // Move funds FROM SAVINGS to CHECKING { system("cls"); string name; long checkPos = 0; long savePos = 0; float savingBalance = 0; string saveAcctName; int i = 0; cin.clear(); fstream saveFile("saving.dat", ios::in | ios::out | ios::beg); fstream checkFile("checking.dat", ios::in | ios::out | ios::beg); cout << "\t\t-=[ Funds Transfer ]=-" << endl; cout << "\t\t-=[ Savings to Checking ]=-" << endl; cout << "Account Name: "; cin.sync(); getline(cin, name); getline(checkFile, checkAcctName); while(name != checkAcctName && !checkFile.fail()) { i++; getline(checkFile, checkAcctName); } getline(saveFile, saveAcctName); while(name != saveAcctName && !saveFile.fail()) { i = 0; i++; getline(saveFile, saveAcctName); } if(name == checkAcctName) { cout << "Amount to transfer: $"; float depAmt = 0; cin >> depAmt; for(int j = 0; j < 13; j++) { char input_number; stringstream converter; checkFile.get(input_number); converter << input_number; converter >> acctNumber[j]; } checkPos = checkFile.tellg(); // if the file is found, get the position of acctBalance and store it in ptrPos checkFile.seekg(checkPos); checkFile >> acctBalance; savePos = saveFile.tellg(); saveFile.seekg(savePos); // sending the cursor in the file to ptrPos + 1 to ignore white space saveFile >> savingBalance; if(savingBalance < depAmt) // if checking account does not have enough funds, exit with NSF code fatal("[!!] Insufficient Funds\n"); acctBalance += depAmt; // can be changed to an overloaded operator savingBalance -= depAmt; // can be changed to an overloaded operator checkFile.seekp(checkPos); // go to position previously set above checkFile << acctBalance; // write new balance to checkFile saveFile.seekp(savePos); // same thing as above comment saveFile << savingBalance; // write new balance to saveFile cout << "New Balance in Checking: $" << acctBalance << endl; // will be removed later cout << "New Balance in Savings: $" << savingBalance << endl; // will be removed later aswell } else fatal("[!!] Linked accounts do not exist.\n"); // if account is not found saveFile.close(); checkFile.close(); } /******************************************************** ******************************************************** SAVING ACCOUNT CODE ********************************************************* *********************************************************/ void Saving::newSavingAccount() { system("cls"); ofstream saveFile("saving.dat", ios::out | ios::app); // For saving savings accounts cout << "\t\t -=[ New Savings Account ]=- \n" << endl; cout << "Name of the main holder to be on account: "; getline(cin, saveAcctName); cout << "Deposit Amount: $"; cin >> initSaveDeposit; if(initSaveDeposit <= 0) { while(initSaveDeposit <= 0) { invalid("[!!]0 or negative value entered.\nPerhaps a typo?\n"); cout << "Deposit amount: $"; cin >> initSaveDeposit; } } if(!saveFile) fatal("[!!] Fatal Error 251: Miscommunication with server\n"); saveFile << saveAcctName << endl; for(int j = 0; j < 13; j++) { acctNumber[j] = (rand() % 10); saveFile << acctNumber[j]; } saveFile << endl; saveFile << initSaveDeposit << endl; saveFile.close(); } void Saving::viewSavingBalance() { string name; int i = 0; fstream saveFile("saving.dat", ios::in | ios::beg); cin.clear(); system("cls"); cout << "\t\t -=[ View Saving Account ]=-\n\n" << endl; cout << "Account Name: "; cin.sync(); getline(cin, name); getline(saveFile, saveAcctName); while(name != saveAcctName && !saveFile.fail()) { i++; getline(saveFile, saveAcctName); } if(name == saveAcctName) { system("cls"); cout << "\t\t -=[ Saving Account Balance ]=-\n\n" << endl; cout << "Account Name: " << saveAcctName << "\n"; cout << "Account Number: "; for(int j = 0; j < 13; j++) { char input_number; stringstream converter; saveFile.get(input_number); converter << input_number; converter >> acctNumber[j]; cout << acctNumber[j]; } // if balance a problem, try the below commented out line // checkFile.ignore(numeric_limits<streamsize>::max(), '\n'); cout << endl; saveFile >> acctBalance; cout << "Balance: $" << fixed << showpoint << setprecision(2) << acctBalance << endl; } else fatal("[!!] Invalid Account\n"); saveFile.close(); getchar(); } // NEED TO WORK ON THIS PORTION TOMORROW AND MONDAY, ADD OVERLOADED OPS FOR ASSIGNMENT!!!!!!! void Saving::transferFromChecking() // This is to take money FROM checking and ADD IT TO SAVING { system("cls"); string name; long savePos = 0; long checkPos = 0; float checkingBalance = 0; string checkAcctName; int i = 0; cin.clear(); fstream saveFile("saving.dat", ios::in | ios::out | ios::beg); fstream checkFile("checking.dat", ios::in | ios::out | ios::beg); cout << "\t\t-=[ Funds Transfer ]=-" << endl; cout << "\t\t-=[ Checking to Savings ]=-" << endl; cout << "Account Name: "; cin.sync(); getline(cin, name); getline(saveFile, saveAcctName); getline(checkFile, checkAcctName); while(name != saveAcctName && name != checkAcctName && !saveFile.fail() && !checkFile.fail()) { i++; getline(saveFile, saveAcctName); getline(checkFile, checkAcctName); } if(name == saveAcctName) { cout << "Amount to transfer: $"; float depAmt = 0; cin >> depAmt; for(int j = 0; j < 13; j++) { char input_number; stringstream converter; saveFile.get(input_number); converter << input_number; converter >> acctNumber[j]; } savePos = saveFile.tellg(); // if the file is found, get the position of acctBalance and store it in ptrPos saveFile.seekg(savePos); saveFile >> acctBalance; checkPos = checkFile.tellg(); checkFile.seekg(checkPos); // if file is found, store current position of the cursor to ptrPos checkFile >> checkingBalance; if(checkingBalance < depAmt) // if checking account does not have enough funds, exit with NSF code fatal("[!!] Insufficient Funds\n"); // Can also place overloaded op here acctBalance += depAmt; // can be changed to an overloaded operator checkingBalance -= depAmt; // can be changed to an overloaded operator saveFile.seekg(savePos); // go to position previously set above saveFile << acctBalance; // write new balance to saveFile checkFile.seekg(checkPos); // same thing as above comment checkFile << checkingBalance; // write new balance to checkFile cout << "New Balance in Savings: $" << acctBalance << endl; // will be removed later cout << "New Balance in Checking: $" << checkingBalance << endl; // will be removed later aswell } else fatal("[!!] Linked accounts do not exist.\n"); // if account is not found saveFile.close(); checkFile.close(); } /******************************************** ******************************************** CHECK AND SAVE CODE ********************************************** **********************************************/ void checkAndSave::newCheckAndSave() { system("cls"); ofstream saveFile("saving.dat", ios::out | ios::app); // For saving savings accounts ofstream checkFile("checking.dat", ios::out | ios::app); // For saving checking accounts cout << "\t -=[ New Checking & Saving Account ]=- \n" << endl; cout << "Name of the main holder to be on account: "; getline(cin, checkAcctName); saveAcctName = checkAcctName; cout << "Checking Deposit Amount: $"; cin >> initCheckDeposit; if(initCheckDeposit <= 0) { while(initCheckDeposit <= 0) { invalid("[!!] 0 or negative amount entered\nMaybe a typo?\n"); cout << "Deposit Amount: $"; cin >> initCheckDeposit; } } cout << "Saving Deposit Amount: $"; cin >> initSaveDeposit; if(initSaveDeposit <= 0) { while(initSaveDeposit <= 0) { invalid("[!!]0 or negative value entered.\nPerhaps a typo?\n"); cout << "Deposit amount: $"; cin >> initSaveDeposit; } } if(!saveFile || !checkFile) fatal("[!!] Fatal Error 251: Miscommunication with server\n"); checkFile << checkAcctName << endl; saveFile << saveAcctName << endl; for(int j = 0; j < 13; j++) { acctNumber[j] = (rand() % 10); checkFile << acctNumber[j]; saveFile << acctNumber[j]; } saveFile << endl; saveFile << initSaveDeposit << endl; checkFile << endl; checkFile << initCheckDeposit << endl; checkFile.close(); saveFile.close(); } void checkAndSave::viewBothBalances() { string name; int i = 0; fstream checkFile("checking.dat", ios::in | ios::beg); fstream saveFile("saving.dat", ios::in | ios::beg); system("cls"); cin.clear(); cout << "\t-=[ Saving & Checking Account Balance ]=-\n\n" << endl; cout << "Account Name: "; cin.sync(); getline(cin, name); getline(checkFile, checkAcctName); saveAcctName = name; /**********************\ | Checking Account portion | | of the checking & savings | | overview | \**********************/ while(name != checkAcctName && !checkFile.fail()) { i++; getline(checkFile, checkAcctName); } system("cls"); if(name != checkAcctName && checkFile.fail()) invalid("\n\n[!!] No Checking Account Found\n"); cout << "\t\t -=[ Checking Account ]=- \n" << endl; cout << "Account Name: " << checkAcctName << "\n"; cout << "Account Number: "; for(int j = 0; j < 13; j++) { char input_number; stringstream converter; checkFile.get(input_number); converter << input_number; converter >> acctNumber[j]; cout << acctNumber[j]; } // if balance a problem, try the below commented out line // checkFile.ignore(numeric_limits<streamsize>::max(), '\n'); cout << endl; checkFile >> acctBalance; cout << "Balance: $" << fixed << showpoint << setprecision(2) << acctBalance << endl; /*********************\ | Saving Account portion | | of the checking & saving | | overview | \*********************/ getline(saveFile, saveAcctName); while(name != saveAcctName && !saveFile.fail()) { i++; getline(saveFile, saveAcctName); } if(name != saveAcctName && saveFile.fail()) invalid("\n\n[!!] No Saving Account Found\n"); if(name == saveAcctName) { cout << "\t\t -=[ Saving Account ]=-\n\n" << endl; cout << "Account Name: " << saveAcctName << "\n"; cout << "Account Number: "; for(int j = 0; j < 13; j++) { char input_number; stringstream converter; saveFile.get(input_number); converter << input_number; converter >> acctNumber[j]; cout << acctNumber[j]; } // if balance a problem, try the below commented out line // checkFile.ignore(numeric_limits<streamsize>::max(), '\n'); cout << endl; saveFile >> acctBalance; cout << "Balance: $" << fixed << showpoint << setprecision(2) << acctBalance << endl; } if(name != saveAcctName && name != checkAcctName && saveFile.fail() && checkFile.fail()) fatal("[!!] No Accounts Have Been Found\n"); checkFile.close(); saveFile.close(); getchar(); } Main.cpp #include <iostream> #include "MainBankClass.h" using namespace std; int main() { Banking bank; Checking check; Saving save; checkAndSave CanS; char choice; choice = bank.menu(); // Call the banking menu switch(choice) { case 'A': choice = bank.newAccountMenu(); switch(choice) { case 'A': check.newCheckingAccount(); break; case 'B': save.newSavingAccount(); break; case 'C': CanS.newCheckAndSave(); break; default: system("cls"); bank.fatal("[!!] Invalid option\n"); break; } break; /***********************************************/ case 'B': choice = bank.getBalanceChoice(); switch(choice) { case 'A': check.viewCheckingBalance(); break; case 'B': save.viewSavingBalance(); break; case 'C': CanS.viewBothBalances(); break; default: bank.fatal("Invalid decision\n"); break; } /*************************************************/ break; case 'C': check.transferFromSaving(); break; case 'D': save.transferFromChecking(); break; case 'E': system("cls"); cout << "\t\t-=[ Disconnecting From System ]=-\n"; cout << "\t\t\t Thank you" << endl; cout << "\t\t Have a nice day!" << endl; exit(1); break; default: system("cls"); bank.invalid("\n\n\n\n\t\t [+] Invalid Selection \n\t\t[+] Disconnecting From System \n\t\t\tGood-bye \n\n\n\n\n\n\n"); exit(1); break; } return 0; }

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  • problem injecting Sessionscoped bean in Managed bean

    - by user310852
    I have a Session scoped bean @SessionScoped public class UserData implements Serializable { private String uid; public String getUid() { return uid; } public void setUid(final String uid) { this.uid = uid; } I'm setting a value in a SessionScoped bean in my stateless session bean public void setOperator(final Operator operator) { userData.setUid(operator.getId()); } When I try to get the object with @Inject I only get null @ManagedBean(name = "RoleController") @SessionScoped public class RoleController { ... @Inject private UserData userData; ... public UserData getUserData() { System.out.println("ID"); System.out.println(userData.getUid()); I have a bean.xml

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  • On reference_wrapper and callable objects

    - by Nicola Bonelli
    Given the following callable object: struct callable : public std::unary_function &lt;void, void&gt; { void operator()() const { std::cout << "hello world" << std::endl; } }; a std::tr1::reference_wrapper< calls through it: callable obj; std::tr1::ref(obj)(); Instead, when the operator() accepts an argument: struct callable : public std::unary_function &lt;int, void&gt; { void operator()(int n) const { std::cout << n << std::endl; } }; std::tr1::bind accepts a reference_wrapper to it as a callable wrapper... callable obj; std::tr1::bind( std::tr1::ref(obj), 42 )(); but what's wrong with this? std::tr1::ref(obj)(42);

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  • Coredump in Multithreading Application in RHEL-5(Help Required)

    - by Chinnu
    I am working on multi-threading application it is dumping frequently.I could not able to analyaze the core.The core is showing like this Core was generated by `thread-process '. Program terminated with signal 6, Aborted. 0 0x00000038f4e30045 in raise () from /lib64/libc.so.6 (gdb) where 0 0x00000038f4e30045 in raise () from /lib64/libc.so.6 1 0x00000038f4e31ae0 in abort () from /lib64/libc.so.6 2 0x00000038f4e681bb in __libc_message () from /lib64/libc.so.6 3 0x00000038f4e72b96 in free () from /lib64/libc.so.6 4 0x000000000046a137 in std::string::substr () 5 0x000000000042c549 in std::operator<< , std::allocator () 6 0x000000000042cc1d in std::operator<< , std::allocator () 7 0x000000000046b069 in std::string::substr () 8 0x000000000046c866 in std::string::substr () 9 0x0000000000431062 in std::operator<< , std::allocator () 10 0x00000038f5a062e7 in start_thread () from /lib64/libpthread.so.0 11 0x00000038f4ece3bd in clone () from /lib64/libc.so.6

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  • Implementing implicitly shared classes outside of Qt

    - by Timothy Baldridge
    I'm familiar with the way Qt uses D-pointers for managing data. How do I do this in my code? I tried this method: 1) move all data into a struct 2) add a QAtomicInt to the struct 3) implement a = operator and change my constructor/deconstructor to check-up on the reference count. The issue is, when I go to do a shallow copy of the object, I get an error about QObject declaring = as private. How then do I accomplish this? Here's an example of my copy operator: HttpRequest & HttpRequest::operator=(const HttpRequest &other) { other.d->ref.ref(); if (!d->ref.deref()) delete d; d = other.d; return *this; } Am I going about this the wrong way?

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  • spring mvc nested model validation

    - by hguser
    I have two models : User,Project public class Project{ private int id; @NotEmpty(message="Project Name can not be empty") private String name; private User manager; private User operator; //getter/setter omitted } public class User{ private int id; private String name; //omit other properties and getter/setter } Now, when I create a new Project, I will submit the following parameters to ProjectController: projects?name=jhon&manager.id=1&operator.id=2... Then I will create a new Project object and insert it to db. However I have to validate the id of the manager and operator is valid,that's to say I will validate that if there is matched id in the user table. So I want to know how to implement this kind of validation?

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  • C++ domain specific embedded language operators

    - by aaa
    hi. In numerical oriented languages (Matlab, Fortran) range operator and semantics is very handy when working with multidimensional data. For example: A(i:j,k,:n) // represents two-dimensional slice B(i:j,0:n) of A at index k unfortunately C++ does not have range operator (:). of course it can be emulated using range/slice functor, but semantics is less clean than Matlab. I am prototyping matrix/tensor domain language in C++ and am wondering if there any options to reproduce range operator. I still would like to rely on C++/prprocessor framework exclusively. So far I have looked through boost wave which might be an suitable option. is there any other means to introduce new operators to C++ DSL?

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  • Trouble assigning a tr1::shared_ptr

    - by Max
    I've got a class that has a tr1::shared_ptr as a member, like so: class Foo { std::tr1::shared_ptr<TCODBsp> bsp; void Bar(); } In member function Bar, I try to assign it like this: bsp = newTCODBsp(x,y,w,h); g++ then gives me this error no match for ‘operator=’ in ‘((yarl::mapGen::MapGenerator*)this)->yarl::mapGen::MapGenerator::bsp = (operator new(40u), (<statement>, ((TCODBsp*)<anonymous>)))’ /usr/include/c++/4.4/tr1/shared_ptr.h:834: note: candidates are: std::tr1::shared_ptr<TCODBsp>& std::tr1::shared_ptr<TCODBsp>::operator=(const std::tr1::shared_ptr<TCODBsp>&) in my code, Foo is actually yarl::mapGen::MapGenerator. What am I doing wrong?

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  • rails: has_many :through + polymorphism validation?

    - by ramonrails
    I am trying to achieve this. Any hints? A project has many users through join model A user has many projects through join model Admin class inherits User class. It also has some Admin specific stuff. Admin like inheritance for Supervisor and Operator Project has one Admin, One supervisor and many operators. Now I want to 1. submit data for project, admin, supervisor and operator in a single project form 2. validate all and show errors on the project form. Project has_many :users, :through = :projects_users User has_many :projects, :through = :projects_users ProjectsUser = :id integer, :user_id :integer, :project_id :integer, :user_type :string ProjectUser belongs_to :project, belongs_to :user, :polymorphic = true Admin < User Supervisor < User Operator < User Is the approach correct? Any and all suggestions are welcome.

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  • Nonstatic conversion functions; Casting different types, e.g. DirectX vector to OpenGL vector

    - by Markus
    I am currently working on a game "engine" that needs to move values between a 3D engine, a physics engine and a scripting language. Since I need to apply vectors from the physics engine to 3D objects very often and want to be able to control both the 3D, as well as the physics objects through the scripting system, I need a mechanism to convert a vector of one type (e.g. vector3d<float>) to a vector of the other type (e.g. btVector3). Unfortunately I can make no assumptions on how the classes/structs are laid out, so a simple reinterpret_cast probably won't do. So the question is: Is there some sort of 'static'/non-member casting method to achieve basically this: vector3d<float> operator vector3d<float>(btVector3 vector) { // convert and return } btVector3 operator btVector3(vector3d<float> vector) { // convert and return } Right now this won't compile since casting operators need to be member methods. (error C2801: 'operator foo' must be a non-static member)

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  • Comparing structs in C++

    - by kamziro
    So in C++ There's a lot of times where you need to make an "index" class. For example: class GameID{ public: string name; int regionid; int gameid; bool operator<(const GameID& rhs) const; } Now, if we were to represent GameID as pair , the operator comparison just comes with it. Is there any other way to get that automatic operator comparison without having to use std::pair< ?

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  • Copy method optimization in compilers

    - by Dženan
    Hi All! I have the following code: void Stack::operator =(Stack &rhs) { //do the actual copying } Stack::Stack(Stack &rhs) //copy-constructor { top=NULL; //initialize this as an empty stack (which it is) *this=rhs; //invoke assignment operator } Stack& Stack::CopyStack() { return *this; //this statement will invoke copy contructor } It is being used like this: unsigned Stack::count() { unsigned c=0; Stack copy=CopyStack(); while (!copy.empty()) { copy.pop(); c++; } return c; } Removing reference symbol from declaration of CopyStack (returning a copy instead of reference) makes no difference in visual studio 2008 (with respect to number of times copying is invoked). I guess it gets optimized away - normally it should first make a copy for the return value, then call assignment operator once more to assign it to variable sc. What is your experience with this sort of optimization in different compilers? Regards, Dženan

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  • Why do I get the error "X is not a member of Y" even though X is a friend of Y?

    - by user1232138
    I am trying to write a binary tree. Why does the following code report error C2039, "'<<' : is not a member of 'btree<T'" even though the << operator has been declared as a friend function in the btree class? #include<iostream> using namespace std; template<class T> class btree { public: friend ostream& operator<<(ostream &,T); }; template<class T> ostream& btree<T>::operator<<(ostream &o,T s) { o<<s.i<<'\t'<<s.n; return o; }

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