AssertUtil { public static void isTrue(boolean b, String message) { if (!b) { throw new IllegalArgumentException(message); } }  static void isTrue(boolean b, String message); static void isFalse(boolean b, String message); static void isNull(Object o, String message); static void notNull(Object o, String message); static void isEqual(int v1, int v2, String message); static void isStrictlyPositive(long value, String message); static void isBetween(double value, double lowerBd, double upperBd, String message);  }
@Test public void testIsTrue_trueValue() { isTrue(true, "The param must be true"); }
@Test(expected = IllegalArgumentException.class) public void testIsTrue_falseValue() { isTrue(false, "The param must be true"); }