Preconditions { public static void assertTrue(boolean argument, String message) { if (!argument) { throw new IllegalArgumentException(message); } }  static void assertNull(Object object, String message); static T assertNotNull(T object, String message); static void assertTrue(boolean argument, String message);  }
@Test public void testAssertTruePass() { Preconditions.assertTrue(true, "should pass"); }
@Test(expected = IllegalArgumentException.class) public void testAssertTrueFail() { Preconditions.assertTrue(false, "should fail"); }