No Matching Function Call - c++

Question

I'm new to C++ and trying to code a HashTable data structure.
I've written it to be generic using templates, and I've included a HashEntry object to use in it to allow for easy quadratic probing for collisions.
The code I have is:
(in a .C file that #include's the below class definition .H file):
HashEntry::HashEntry()
{
this->isActive = false;
}
And the associated .H file with the class definitions is:
#include <iostream>
#include <string>
#include "Entry.C"
using namespace std;
#define Default_Size 50000
class HashEntry;
template <class T> class HashTable
{
private:
int size;
int occupied;
T array[Default_Size];
public:
HashTable();
int Size();
void Add(T t);
void DebugAdd(T t, int index);
T* Get(string index);
/* How do I declare the existence of HashEntry BEFORE here? */
int FindNextOpen(HashEntry he); // Only works for hash_entry objects!
int Hash(string str);
void Rehash();
};
class HashEntry
{
private:
Entry e;
bool isActive;
public:
HashEntry();
HashEntry(Entry e);
bool IsActive();
Entry GetEntry();
};
Whenever I try and compile everything, I get the error for the HashEntry constructor above:
"no matching function for call to Entry::Entry()" ... "candidates are.....".
I have no idea what it means -- when I try to include a default Entry() constructor (my first interpretation), it throws more errors.
Thanks for the help!
UPDATE -- ENTRY.C:
#include "Entry.H"
/* ***Entry Methods*** */
/*
* Overloaded Entry obejct constructor that provides a string value.
*/
Entry::Entry(string s)
{
this->value = s;
this->count = 0;
}
/*
* Returns the number of times this Entry has been accessed/
* found.
*/
int Entry::Count()
{ return this->count; }
/*
* Returns the string value stored in the Entry object.
*/
string Entry::Value()
{ return this->value; }

Answer 1

And the associated .H file with the class definitions is:
#include <iostream>
#include <string>
#include "Entry.C"
Whoa! Never, ever #include a source file in a header.
Your Entry.C should not exist. Instead define the constructor in your header, inside the class definition:
class HashEntry
{
private:
Entry e;
bool isActive;
public:
HashEntry() : isActive(true) {}
...
}
One thing that you haven't shown us is the definition of the class Entry. That is one of the sources of your problem. It's a bit hard to pin down your problem when you didn't show us the very thing that is causing it.

Answer 2

I found the problem.
The error message says there is not matching function call for "Entry::Entry()". Because in no case was I actually creating Entry objects I had no idea what it meant.
I tried adding an explicit default constructor for class Entry and it resolved.
Thanks for the help everyone!