Answer Happy

public class Main{ public static void main(String [] args){ Persegi persegi = newPersegi(); persegi.sisi = 8; System.out.println(persegi.computeArea()); }}
public interface BangunDatar { public float computeArea(); public float computeAround();}
public class Persegi implements BangunDatar { public int sisi;
public Persegi(){} public Persegi(int sisi) { super(); this.sisi = sisi; }
@Override public float computeArea() { // TODO Auto-generated methodstub returnthis.sisi*this.sisi; }
@Override public float computeAround() { // TODO Auto-generated methodstub return 4*this.sisi; }
}
public class BangunRuang implements BangunDatar {
@Override public float computeArea() { // TODO Auto-generated methodstub return 0; }
@Override public float computeAround() { // TODO Auto-generated methodstub return 0; }
public float computeVolume() { return 0; }
}
public class Kubus extends BangunRuang implements BangunDatar{ public int rusuk;
public Kubus(int rusuk) { super(); this.rusuk = rusuk; }
@Override public float computeArea() { // TODO Auto-generated methodstub return6*this.rusuk*this.rusuk; }
@Override public float computeAround() { // TODO Auto-generated methodstub return 12*this.rusuk; }
@Override public float computeVolume() { // TODO Auto-generated methodstub returnthis.rusuk*this.rusuk*this.rusuk; };}
Find 2 code smell in this code