Programmieren in Java - HostFiXX.de

Programmieren in Java
public abstract double umfang();
public abstract double flaeche();
}
import java.lang.*;
public class Kreis extends GeomObjekt
{
// Instanzvariable
private double r; // Radius
// Konstruktoren
public Kreis()
{
this(0.0,0.0,1.0);
}
public Kreis(double r)
{
this(0.0,0.0,r);
}
public Kreis(double x, double y, double r)
{
super();
super.setzeX(x);
super.setzeY(y);
this.setzeR(r);
}
// Instanzmethoden
public double holeR()
{
return r;
}
public void setzeR(double r)
{
this.r = (r >= 0.0 ? r : -r);
}
public double umfang()
{
double u = 2 * r * Math.PI;
return u;
}
public double flaeche()
{
return r * r * Math.PI;
}
public String toString()
{
return "Kreis: (" + holeX() + ", " + holeY() +
") " + "r = " + r;
}
}
import java.lang.*;
public class Rechteck extends GeomObjekt
{
// Instanzvariable
private double breite, hoehe;
// Konstruktoren
public Rechteck()
{
this(0.0,0.0,1.0,1.0);
}
public Rechteck(double breite, double hoehe)
{
this(0.0,0.0,breite,hoehe);
}
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