Constructors and Destructors

class employee {

public: // ignore this for now

char *name_p;

int base_pay_p;

int year_started_p;

int leave_time_p;

employee();

~employee();

void set_name(char *name) {name_p = strdup(name);}

char *name() { return name_p; }

void set_base_pay(int pay) { base_pay_p = pay; }

int base_pay() { return base_pay_p; }

};

employee::employee() { // Constructor!

name_p = NULL;

base_pay_p = year_started_p = leave_time_p = 0;

}

employee::~employee() { // Destructor!

if (name_p != NULL)

free(name_p);

}

main()

{

employee e; // Constructor is called!

employee e2; // Constructor again!

e.set_name(“John Doe”);

e.set_base_pay(40000);

printf(“Name is %s; base pay is %d\n”, e.name(),

e.base_pay());

e2.name_p = 0xdeadbeef;

} // Destructors are called for e and e2!

Uh oh! This program will crash when e2’s destructor tries to call free(0xdeadbeef)! Wouldn’t it be nice if we could somehow protect our internal variables from outside access? I’m so glad you asked!!

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