different type of object

Header File: Point.h

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/* The Point class Header file (Point.h) */ #ifndef POINT_H #define POINT_H class Point { private: int x, y; // Private data members public: Point(int x = 0, int y = 0); // Constructor with default arguments int getX() const; // Getter void setX(int x); // Setter int getY() const; void setY(int y); void setXY(int x, int y); void print() const; }; #endif

Implementation File: Point.cpp

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/* The Point class Implementation file (Point.cpp) */ #include "Point.h" #include <iostream> using namespace std; // Constructor - The default values are specified in the declaration Point::Point(int x, int y) : x(x), y(y) { } // Getters int Point::getX() const { return x; } int Point::getY() const { return y; } // Setters void Point::setX(int x) { this->x = x; } void Point::setY(int y) { this->y = y; } // Public Functions void Point::setXY(int x, int y) { this->x = x; this->y = y; } void Point::print() const { cout << "Point @ (" << x << "," << y << ")"; }

A Test Driver: TestPoint.cpp

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/* A test driver program (TestPoint.cpp) */ #include "Point.h" #include <iostream> using namespace std; int main() { // Instances (Objects) Point p1; // Invoke default constructor // OR Point p1 = Point(); NOT Point p1(); Point p2(2, 2); // Invoke constructor // OR Point p2 = Point(2, 2); p1.print(); // Point @ (0,0) cout << endl; p2.print(); // Point @ (2,2) cout << endl; // Object Pointers with dynamic allocation Point * ptrP3, * ptrP4; // Declare two Point pointers ptrP3 = new Point(); // Dynamically allocate storage via new // with default constructor ptrP4 = new Point(4, 4); ptrP3->print(); // Point @ (0,0) // prtPoint1->print() is the same as (*ptrP3).print() cout << endl; ptrP4->print(); // Point @ (4,4) cout << endl; delete ptrP3; // Remove storage via delete delete ptrP4; // Object Reference (Alias) Point & p5 = p2; // Reference (alias) to an existing object p5.print(); // Point @ (2,2) cout << endl; /******************** * ARRAYS * ********************/ // Array of Objects - Static Memory Allocation Point ptsArray1[2]; // Array of Point objects // Use default constructor for all elements of the array ptsArray1[0].print(); // Point @ (0,0) cout << endl; ptsArray1[1].setXY(11, 11); (ptsArray1 + 1)->print(); // Point @ (11,11) // same as ptsArray1[1].print() cout << endl; Point ptsArray2[3] = {Point(21, 21), Point(22, 22), Point()}; // Initialize array elements via constructor ptsArray2[0].print(); // Point @ (21,21) cout << endl; (ptsArray2 + 2)->print(); // Point @ (0,0) // same as ptsArray2[2].print() cout << endl; // Array of Object Pointers - Need to allocate elements dynamically Point * ptrPtsArray3 = new Point[2]; ptrPtsArray3[0].setXY(31, 31); ptrPtsArray3->print(); // Point @ (31,31) // same as ptrPtsArray3[0].print() cout << endl; (ptrPtsArray3 + 1)->setXY(32, 32); // same as ptrPtsArray3[1].setXY(32, 32) ptrPtsArray3[1].print(); // Point @ (32,32) cout << endl; delete[] ptrPtsArray3; // Free storage // C++ does not support Array of References // Point & pts[2] = {p1, p2}; // error: declaration of 'pts' as array of references }