constructors and destructors

A constructor is a method that gets called immediately when an object is allocated (on the stack or the heap).

It is the constructor’s job to initialize the object’s attributes to sensible initial values.

A constructor may have parameters that can inform the initial values. A constructor has the same name as the class.

You can have more than one constructor.

A constructor has no return type and no return statement.

C++ gives every class a default (implicit) constructor that takes no arguments, and does nothing.









A destructor is a method that gets called immediately when an object is de-allocated.

It is the destructor’s job tidy up. It may need to deallocate memory on the heap, or close a file.

A destructor may not have parameters.

A destructor has the same name as the class, preceded with a “∼”. You can have only one constructor.

A constructor has no return type and no return statement.

C++ gives every class a default (implicit) destructor that does nothing.

class Point 

{ 

// sample class private:

float x; // stores the x coordinate 

float y; // stores the y coordinate

public:

Point(); //the constructor 

void setX(float newX); 

void setY(float newY); 

float getX();

float getY();

~Point(); //the destructor

};





Point::Point()

{

x = 0;

y = 0;

}













Point::~Point()

{ 

//do nothing

}