#include <iostream>
#include <cstdlib>
#include <new>
using namespace std;
class Point {
int x, y;
public:
Point() {x = y = 0;}
Point(int px, int py) {
x = px;
y = py;
}
void show() {
cout << x << " ";
cout << y << "\n";
}
void *operator new(size_t size);
void operator delete(void *p);
void *operator new[](size_t size);
void operator delete[](void *p);
};
// new overloaded relative to Point.
void *Point::operator new(size_t size)
{
void *p;
cout << "In overloaded new.\n";
p = malloc(size);
if(!p) {
bad_alloc ba;
throw ba;
}
return p;
}
// delete overloaded relative to Point.
void Point::operator delete(void *p)
{
cout << "In overloaded delete.\n";
free(p);
}
// new overloaded for Point arrays.
void *Point::operator new[](size_t size)
{
void *p;
cout << "Using overload new[].\n";
p = malloc(size);
if(!p) {
bad_alloc ba;
throw ba;
}
return p;
}
// delete overloaded for Point arrays.
void Point::operator delete[](void *p)
{
cout << "Freeing array using overloaded delete[]\n";
free(p);
}
int main()
{
Point *p1, *p2;
int i;
try {
p1 = new Point (10, 20); // allocate an object
} catch (bad_alloc xa) {
cout << "Allocation error for p1.\n";
return 1;;
}
try {
p2 = new Point [10]; // allocate an array
} catch (bad_alloc xa) {
cout << "Allocation error for p2.\n";
return 1;;
}
p1->show();
for(i=0; i<10; i++)
p2[i].show();
delete p1; // free an object
delete [] p2; // free an array
return 0;
}
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