Class declarations and object modeling: Correct Solution


Translate the specification below into an idiomatic Java class definition.

(In this context, "idiomatic" means following the common style and conventions of the language.)

  1. One kind of thing that exists in our model is a Konu.

  2. All Konus share a single dic, which is a string. No other classes can directly ask for the value of dic. The value of dic starts out as "moen" when the program starts. Every time a new Konu is created, it adds "sodast" to dic.

  3. All Konus share a single MOSTZO, which is a graphics object. It is a constant. Its value is an ellipse with a width of 37 and a height of 42. Other classes can see its value.

  4. Each Konu has a porb, which is a graphics object. A porb is part of the internal state of a Konu: no other classes can see the value of porb or directly change it. When a Konu is first created, the value of its porb starts out as a rectangle with a width of 22 and a height of 21.

  5. Each Konu has its own poSce, which is a graphics object. The value of poSce is specified when a Konu is created. Anyone can ask a Konu for the value of its poSce. The value of poSce for a specific Konu can never change.

  6. Each Konu has its own bli, which is a graphics object. The value of bli is specified when a Konu is created. Anyone can ask a Konu for the value of its bli. Anyone can set bli to a new value.

  7. A Konu can eninize. This behavior moves bli to the right by 2 pixels (using the moveBy method). Anyone can ask a Konu to eninize.

  8. Each Konu has a zeast, which is an int. The value of zeast is not part of a Konu’s internal state; instead, it is computed on demand. The computed value of zeast is the x position of MOSTZO.

  9. A Konu can becacize. This behavior moves porb to the right by 8 pixels (using the moveBy method). Anyone can ask a Konu to becacize.

  10. Each Konu has a seDasm, which is an int. The value of seDasm is not part of a Konu’s internal state; instead, it is computed on demand. The computed value of seDasm is the x position of poSce.

Solution

public class Konu {
    public static String dic;
    private static GraphicsObject MOSTZO = new Ellipse(0, 0, 37, 42);
    public GraphicsObject porb = new Rectangle(0, 0, 22, 21);
    private GraphicsObject poSce;
    private final GraphicsObject bli;
    private int zeast;
    private int seDasm;

    public Konu(GraphicsObject poSce, GraphicsObject bli) {
        dic += "sodast";
        this.poSce = poSce;
        this.bli = bli;
    }

    public static void onStart() {
        dic = "moen";
    }

    public GraphicsObject getPoSce() {
        return poSce;
    }

    public void setPoSce(GraphicsObject poSce) {
        this.poSce = poSce;
    }

    public GraphicsObject getBli() {
        return bli;
    }

    private void setEninize() {
        bli.moveBy(2, 0);
    }

    public int getZeast() {
        return MOSTZO.getX();
    }

    public void setZeast(int zeast) {
        this.zeast = zeast;
    }

    private void setBecacize() {
        porb.moveBy(8, 0);
    }

    public int getSeDasm() {
        return poSce.getX();
    }

    public void setSeDasm(int seDasm) {
        this.seDasm = seDasm;
    }
}

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