Rectangle r = new Rectangle(100, 20); System.out.println("original: " + r.toString()); modifyWidth(r, new Integer(300)); System.out.println("modified: " + r.toString());
Field widthField; Integer widthValue; Class c = r.getClass(); try { widthField = c.getField("width"); widthField.set(r, widthParam); } catch (NoSuchFieldException e) { System.out.println(e); } catch (IllegalAccessException e) { System.out.println(e); }