Das Schlüsselwort this

class Pwr {
    double b;
    int e;
    double val;

    Pwr(double base, int exp) {
        b = base;
        e = exp;
        val = 1;
        if (exp == 0) return;
        for (; exp > 0; exp--) val = val * base;
    }

    double get_pwr() {
        return val;
    }
}

class Pwr {
    double b;
    int e;
    double val;

    Pwr(double b, int e) {
        this.b = b;
        this.e = e;
        this.val = 1;
        if (e == 0) return;
        for (; e > 0; e--) this.val = this.val * b;
    }

    double get_pwr() {
        return this.val;
    }
}

class Pwr {
    double b;
    int e;
    double val;

    Pwr(double base, int exp) {
        this.b = base;
        this.e = exp;
        this.val = 1;
        if (exp == 0) return;
        for (; exp > 0; exp--) this.val = this.val * base;
    }

    double get_pwr() {
        return this.val;
    }
}

class DemoPwr {
    public static void main(String args[]) {
        Pwr x = new Pwr(4.0, 2);
        Pwr y = new Pwr(2.5, 1);
        Pwr z = new Pwr(5.7, 0);
        System.out.println(x.b + " raised to the " + x.e +
            " power is " + x.get_pwr());
        System.out.println(y.b + " raised to the " + y.e +
            " power is " + y.get_pwr());
        System.out.println(z.b + " raised to the " + z.e +
            " power is " + z.get_pwr());
    }
}