fajn, začínáte to chápat 
Když si prohlídnete objektové návrhové vzory, gettery a settery se v nich většinou nevyskytují, přesto že implementují relativně složité chování.
Gamma and spol - "Design Patterns: Elements of Reusable Object-Oriented Software"
Priklad na vzor observer:
#include <iostream>
#include <vector>
#include <time.h>
#include <sys/types.h>
#include <sys/timeb.h>
#include <string.h>
using namespace std ;
class Subject;
class Observer
{
public:
Observer() {};
~Observer() {};
virtual void Update(Subject* theChangeSubject) = 0;
};
class Subject
{
public:
Subject() {};
virtual ~Subject() {};
virtual void Attach(Observer*);
virtual void Detach(Observer*);
virtual void Notify();
private:
vector<Observer*> _observers;
};
void Subject::Attach (Observer* o)
{
_observers.push_back(o);
}
void Subject::Detach (Observer* o)
{
int count = _observers.size();
int i;
for (i = 0; i < count; i++) {
if(_observers[i] == o)
break;
}
if(i < count)
_observers.erase(_observers.begin() + i);
}
void Subject::Notify ()
{
int count = _observers.size();
for (int i = 0; i < count; i++)
(_observers[i])->Update(this);
}
class ClockTimer : public Subject
{
public:
ClockTimer() { _strtime( tmpbuf ); };
int GetHour();
int GetMinute();
int GetSecond();
void Tick();
private:
char tmpbuf[128];
};
/* Set time zone from TZ environment variable. If TZ is not set,
* the operating system is queried to obtain the default value
* for the variable.
*/
void ClockTimer::Tick()
{
_tzset();
// Obtain operating system-style time.
_strtime( tmpbuf );
Notify();
}
int ClockTimer::GetHour()
{
char timebuf[128];
strncpy(timebuf, tmpbuf, 2);
timebuf[2] = NULL;
return atoi(timebuf);
}
int ClockTimer::GetMinute()
{
char timebuf[128];
strncpy(timebuf, tmpbuf+3, 2);
timebuf[2] = NULL;
return atoi(timebuf);
}
int ClockTimer::GetSecond()
{
char timebuf[128];
strncpy(timebuf, tmpbuf+6, 2);
timebuf[2] = NULL;
return atoi(timebuf);
}
class DigitalClock: public Observer
{
public:
DigitalClock(ClockTimer *);
~DigitalClock();
void Update(Subject *);
void Draw();
private:
ClockTimer *_subject;
};
DigitalClock::DigitalClock (ClockTimer *s)
{
_subject = s;
_subject->Attach(this);
}
DigitalClock::~DigitalClock ()
{
_subject->Detach(this);
}
void DigitalClock::Update (Subject *theChangedSubject)
{
if(theChangedSubject == _subject)
Draw();
}
void DigitalClock::Draw ()
{
int hour = _subject->GetHour();
int minute = _subject->GetMinute();
int second = _subject->GetSecond();
cout << "Digital time is " << hour << ":"
<< minute << ":"
<< second << endl;
}
class AnalogClock: public Observer
{
public:
AnalogClock(ClockTimer *);
~AnalogClock();
void Update(Subject *);
void Draw();
private:
ClockTimer *_subject;
};
AnalogClock::AnalogClock (ClockTimer *s)
{
_subject = s;
_subject->Attach(this);
}
AnalogClock::~AnalogClock ()
{
_subject->Detach(this);
}
void AnalogClock::Update (Subject *theChangedSubject)
{
if(theChangedSubject == _subject)
Draw();
}
void AnalogClock::Draw ()
{
int hour = _subject->GetHour();
int minute = _subject->GetMinute();
int second = _subject->GetSecond();
cout << "Analog time is " << hour << ":"
<< minute << ":"
<< second << endl;
}
int main(void)
{
ClockTimer timer;
DigitalClock digitalClock(&timer;);
AnalogClock analogClock(&timer;);
timer.Tick();
return 0;
}
Upriamujem pozornost na tento kus kodu:
class ClockTimer : public Subject
{
public:
ClockTimer() { _strtime( tmpbuf ); };
int GetHour();
int GetMinute();
int GetSecond();
void Tick();
private:
char tmpbuf[128];
};
Podobne je na tom mediator. To su dva vzory, ktore si pamatam, ze su tam getre. Lebo z podstaty musia byt. Cele je to prave o zistovani vnutorneho stavu objektu, co by sa podla tunajsich diskuterov nemalo robit. Takze akekolvek obicyklovanie getrov by bolo len zistovanie vnutorneho stavu aj tak.
Mozno, ked si prezriem ine vzory, nedopadnu lepsie. Taky builder je o setroch, len v bledoruzovom.
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