CharArrayWriter output = new CharArrayWriter();
assertNotNull(output);
TestHelperOwner owner = new TestHelperOwner();
assertNotNull(owner);
owner.setName("Jane Smith");
TestHelperCar car = new TestHelperCar();
car.setKms(18768);
car.setNumberDoors("5");
car.setVin("A880BBC64");
owner.addTestHelperVehicle(car);
TestHelperBoat boat = new TestHelperBoat();
boat.setKms(7248);
boat.setVin("6674C");
boat.setTopSpeedInKnots("54");