Kapan sampeyan kudu nggunakake getter lan setter (lan kapan ora)?

Question

Accepted Answer

Getter/setter mbukaaken akses terkontrol menyang medan, nanging adat umum nambah siji *kanggo saben medan* punika antipatron. Pitakonan nyata punika: apa aksesore nambahi nilai, utawa malah mung nambahi medan public nganggo langkah-langkah ekstra?

## Nalika setter diperlokake

```java
public class Thermostat {
    private int target;
    public void setTarget(int t) {     // setter adds VALIDATION
        if (t < 5 || t > 30)
            throw new IllegalArgumentException("out of range");
        this.target = t;
    }
    public int getTarget() { return target; }
}
```

Dene setter nglakokake invariant — punika patut.

## Nalika pung swara bae

```java
// Anti-pattern: "encapsulation theatre"
public class Point {
    private int x, y;
    public int getX() { return x; }    public void setX(int x){ this.x=x; }
    public int getY() { return y; }    public void setY(int y){ this.y=y; }
}
// This is no safer than public fields — and now x,y can change anytime.
```

## Pikiran sing luwih apik: kandha, aja takon

Saranipun mbukaaken negara supaya panggilan bisa manipulasi, mbukaake *tumindak*:

```java
account.withdraw(100);          // ✅ behavior protects the rule
// vs
account.setBalance(account.getBalance() - 100);  // ❌ logic leaks to caller
```

## Mengapa iku penting

Setter ing saben medan mung rada luwih apik tinimbang nggawe medan public — ngenalake raos enkapsulasi palsu nalika ngidini sapa bae pemanggil ngowahi negara kanthi bebas.

Rancang watara tumindak ("kandha, aja takon") ndadekake invariant tetep ing objek, kurangi kesesuaian, lan asring mbukak manawa akeh medan kudu ora kelangan setter.