Robot { public Robot() {} Robot(); Machine location(); void moveTo(Machine location); void pick(); String bin(); void release();  }
@Test public void testRobot() { Machine sorter = new Machine("Sorter", "left"); sorter.put("chips"); Machine oven = new Machine("Oven", "middle"); Robot robot = new Robot(); assertEquals("chips", sorter.bin()); assertNull(oven.bin()); assertNull(robot.location()); assertNull(robot.bin()); robot.moveTo(sorter); robot.pick(); robot.moveTo(oven); robot.release(); assertNull(robot.bin()); assertEquals(oven, robot.location()); assertNull(sorter.bin()); assertEquals("chips", oven.bin()); }