### Question:
Conditions { public static void nonNull(@Nullable Object obj) { nonNull(obj, null); }  static void isTrue(boolean test, @Nullable Object message); static void isTrue(boolean test); static void isTrue(boolean test, @NotNull String message, @Nullable Object... args); static void nonNull(@Nullable Object obj); static void nonNull(@Nullable Object obj, @Nullable Object message);  }### Answer:
@Test void testNonNull() { Assertions.assertThrows(NullPointerException.class, () -> Conditions.nonNull(null)); }