Is it correct to use setters in constructor ?

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Hello, I have a question about setters in constructor. I make a class "Artefacts" and a constructor like this :

public Artefacts(int serialNumber, String culture, int century){

    this.serialNumber = serialNumber;
    this.culture = culture;
    this.century = century;
}

Is it correct to use setters in the constructor like this ? :

public Artefacts(int serialNumber, String culture, int century){

    setSerialNumber(serialNumber);
    setCulture(culture);
    setCentury(century);
}

I find that better than the first code.

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Thomas

niveau Bayreuth, Bayreuth, Germany

23 février 2023, 15:18

utile

It's not wrong. The extra resource usage is just not necessary. Setters and getters are used to encapsulate properties of a class. Means to protect access to these properties from outside the class. Inside of the class you always have access to everything and you always have to possibility to change things as you wish.

.AdaLove_

niveau France, France, France

Expert

23 février 2023, 19:20

Hello, thanks you for this answer. Why in this case using setters in the method consumes more resources?

Thomas

niveau Bayreuth, Bayreuth, Germany

23 février 2023, 21:39

In addition to the minimal tasks the code has to do the bytecode needs instructions to jump to the subroutine, here it needs to create a local variable and assign it a value. To see what I mean I created two mini programs a)

public class Solution {
    int val;

    public Solution(int val) {
        this.val = val;
    }
}

and b)

public class Solution {
    int val;

    public Solution(int val) {
        setVal(val);
    }

    public void setVal(int val) {
        this.val = val;
    }
}

I compiled both and then ran the decompiler. That gave following bytecode instructions a)

public cg_test.Solution(int);
  Code:
     0: aload_0
     1: invokespecial #1                  // Method java/lang/Object."<init>":()V
     4: aload_0
     5: iload_1
     6: putfield      #7                  // Field val:I
     9: return

public cg_test.Solution(int);
  Code:
     0: aload_0
     1: invokespecial #1                  // Method java/lang/Object."<init>":()V
     4: aload_0
     5: iload_1
     6: invokevirtual #7                  // Method setVal:(I)V
     9: return

public void setVal(int);
  Code:
     0: aload_0
     1: iload_1
     2: putfield      #13                 // Field val:I
     5: return

in a) you just need an iload (load the int) and a putfield (save it in an instance variable) b) in addition to a) you need an invokevirtual (the jump to the sub), another aload, an iload and a return) That's what I call it needs more resources