}

    // Test edge cases to understand the validation behavior
    public void test_edgeCaseBehavior() {
        String[] edgeCases = { "0 0 25 * * ?", // Invalid day of month
                "0 60 * * * ?", // Invalid minute
                "0 0 0 32 1 ?", // Invalid day
                "0 0 0 1 13 ?", // Invalid month
        };

        for (String cron : edgeCases) {
            boolean result = validator.determineValid(cron);

        testBoundaryValue(1L);
        testBoundaryValue(-1L);

        // Test one second boundaries
        testBoundaryValue(1000L);
        testBoundaryValue(-1000L);

        // Test one minute boundaries
        testBoundaryValue(60000L);
        testBoundaryValue(-60000L);

        // Test one hour boundaries
        testBoundaryValue(3600000L);
        testBoundaryValue(-3600000L);

    }
  }


  @J2ktIncompatible // slow enough to cause flakiness
  @GwtIncompatible // far too slow
  public void testSqrtOfPerfectSquareAsDoubleIsPerfect() {
    // This takes just over a minute on my machine.
    for (long n = 0; n <= LongMath.FLOOR_SQRT_MAX_LONG; n++) {
      long actual = (long) Math.sqrt((double) (n * n));
      assertTrue(actual == n);
    }
  }