/** Triangles rectangles */ public class RecTriangle extends Triangle implements Form, Transformable { private double sideB,sideC; private double hypo; public RecTriangle(double b,double c) { sideB=b; sideC=c; hypo = Math.sqrt(b*b + c*c); } public double area() { return sideB * sideC / 2; } public double[] getSides () { double[] s=new double[3]; s[0]=hypo; s[1]=sideB; s[2]=sideC; return s; } public String toString() { return "TrRect" + super.toString(); } public void enlarge(double factor) { if (factor > 0) { sideB *= factor; sideC *= factor; hypo *= factor; } else System.err.println( "impossible to zoom with a non positive factor!"); } public static void main(String args[]) { RecTriangle t = new RecTriangle(3.0,4.0); System.out.println(t + " perimeter: " + t.perimeter() + " area: "+ t.area()); t.enlarge(2); System.out.println(t + " perimeter: " + t.perimeter() + " area: "+ t.area()); } }