### Question:
Fibo { public static int fibo(int n) { if (n < 0) { throw new IllegalArgumentException("n must be positive"); } if (n <= 1) { return n; } return fibo(n - 1) + fibo(n - 2); }  static int fibo(int n);  }### Answer:
@Test(name = "validate the fib suite - exception expected") public void testFibException() { assumeThat(expectedException).isNotNull(); assertWhen((p) -> Fibo.fibo(p), x).throwException( instanceOf(expectedException)); }