Please review two corrections for java.time

roger riggs roger.riggs at oracle.com
Tue Sep 10 14:08:01 UTC 2013


Hi Peter,

Point taken about the edge cases, I'm not sure it will occur in practice
but I updated the test to retry if the time changes by more than 15 minutes.
There are likely to be other existing tests that do not taken into account
DST changes but it is not a high priority now to find and fix them.

http://cr.openjdk.java.net/~rriggs/webrev-localtime-now-8023639/

Thanks, Roger

On 9/10/2013 2:43 AM, Peter Levart wrote:
> On 09/09/2013 09:42 PM, roger riggs wrote:
>> Hi Peter,
>>
>> Right, max doesn't solve the issue but I'm not keen on a test that 
>> retries
>> until it gets a better answer.
>
> Hi Roger,
>
> If java.time logic is correct, it should only ever retry once when 
> roll-over or DST jump-back happens, so the test could be made to fail 
> if it tries to retry the 2nd time, indicating unexpected behaviour. 
> The "jumps" in LocalTime should be very far-apart so the test should 
> only encounter one of them, if any.
>
>>
>> Adding nanosPerDay if the difference comes out negative would adjust
>> for the crossing of midnight and not require looping on a more complex
>> test condition.
>
> That's ok for midnight roll-over, but what about DST jumps? They only 
> happen two times a year, so you expect the test will never encounter them?
>
> Regards, Peter
>
>>
>> The longish delay in the now() method is due to first-time initialization
>> that reads the timezone data file.  Introducing the loop it would change
>> the test condition so that it is not testing the 'cold' startup.
>> However, the purpose of the test in not to measure the initialization 
>> overhead
>> so  adding an extra sampling of now(Clock) before the test will 
>> remove the first time
>> initialization.
>>
>> Updated webrev at:
>> http://cr.openjdk.java.net/~rriggs/webrev-localtime-now-8023639/
>>
>> Thanks, Roger
>>
>>
>> On 9/9/2013 11:14 AM, Peter Levart wrote:
>>>
>>> On 09/09/2013 03:12 PM, roger riggs wrote:
>>>> Hi Peter,
>>>>
>>>> The possible wrap-around caused by crossing midnight is handled by 
>>>> Math.max
>>>> so a retry is not needed.
>>>>
>>>> Math.abs(test.toNanoOfDay() - expected.toNanoOfDay())
>>>
>>> Hi Roger,
>>>
>>> In case there is a wrap-around, the 'diff' is much more than 
>>> 500,000,000 ns (about 24*60*60*1,000,000,000 ns - delay), which 
>>> fails the test.
>>>
>>> But what do you think about testing before <= test <= after ? It 
>>> should not be timing dependent, like it is now. Does it test the 
>>> same thing?
>>>
>>> Regards, Peter
>>>
>>>>
>>>> Thanks, Roger
>>>>
>>>>
>>>>
>>>>
>>>> On 9/9/2013 2:14 AM, Peter Levart wrote:
>>>>> On 09/06/2013 07:58 PM, roger riggs wrote:
>>>>>> Please review for two corrections:
>>>>>>
>>>>>> -  The java/time/tck/java/time/TCKLocalTime test failed on a slow 
>>>>>> machine;
>>>>>>     the test should be more lenient.   The test is not 
>>>>>> appropriate for a conformance test
>>>>>>     and is moved to java/time/test/java/time/TestLocalTime.
>>>>>>
>>>>>> - The javadoc for the JapaneseEra.MEIJI era should indicate the 
>>>>>> start date is 1868-01-01
>>>>>>   to be consistent with java.util.Calendar.  Note that java.time 
>>>>>> does not permit dates before Meiji 6
>>>>>>   to be created since the calendar is not clearly defined until 
>>>>>> then.
>>>>>>
>>>>>> Webrev: 
>>>>>> http://cr.openjdk.java.net/~rriggs/webrev-localtime-now-8023639/
>>>>>>
>>>>>> Thanks, Roger
>>>>>>
>>>>>>
>>>>> Hi Roger,
>>>>>
>>>>> Although very in-probable, the test can fail when 'expected' is 
>>>>> sampled before and 'test' is sampled after midnight. I'm guessing 
>>>>> the test is trying to prove that LocalTime.now() is equivalent to 
>>>>> LocalTime.now(Clock.systemDefaultZone()), right?
>>>>>
>>>>> In that case, what about the following:
>>>>>
>>>>>     public void now() {
>>>>>         LocalTime before, test, after;
>>>>>         do {
>>>>>             before = LocalTime.now(Clock.systemDefaultZone());
>>>>>             test = LocalTime.now();
>>>>>             after = LocalTime.now(Clock.systemDefaultZone());
>>>>>           // retry in case the samples were obtained around midnight
>>>>>         } while (before.compareTo(after) > 0);
>>>>>
>>>>>         assertTrue(before.compareTo(test) <= 0 && 
>>>>> test.compareTo(after) <= 0);
>>>>>     }
>>>>>
>>>>>
>>>>> Regards, Peter
>>>>>
>>>>
>>>
>>
>




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