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From: Peter K on 2 Mar 2010 02:09
Hi

I have a c# application which reads data from a database. Some of the data
is a "time" which is actually a c# "ticks" value (written to the db by
another c# application).

Now I am writing a java application, which collects data and writes it to
the database for the c# application to read. So how do I convert a java
"Date" to a value which the c# application can interpret as "ticks"?


Thanks,
Peter

From: Frank Langelage on 2 Mar 2010 03:04
On 02.03.10 08:09, Peter K wrote:
> Hi
>
> I have a c# application which reads data from a database. Some of the
> data is a "time" which is actually a c# "ticks" value (written to the db
> by another c# application).
>
> Now I am writing a java application, which collects data and writes it
> to the database for the c# application to read. So how do I convert a
> java "Date" to a value which the c# application can interpret as "ticks"?
>

First you should use a more common DB schema instead of this proprietary
one.

Second you should have provided the definition of ticks:
From MSDN:
A single tick represents one hundred nanoseconds or one ten-millionth of
a second. There are 10,000 ticks in a millisecond.
The value of this property represents the number of 100-nanosecond
intervals that have elapsed since 12:00:00 midnight, January 1, 0001.


java.util.Date has a constructor public Date(long date) with date as the
number of milliseconds since January 1, 1970, 00:00:00 GMT.
So this should be no problem for a programmer to solve this now.
From: Peter K on 2 Mar 2010 03:44


"Frank Langelage" <frank(a)lafr.de> wrote in message
news:7v3v49Fsj9U1(a)mid.individual.net...
> On 02.03.10 08:09, Peter K wrote:
>> Hi
>>
>> I have a c# application which reads data from a database. Some of the
>> data is a "time" which is actually a c# "ticks" value (written to the db
>> by another c# application).
>>
>> Now I am writing a java application, which collects data and writes it
>> to the database for the c# application to read. So how do I convert a
>> java "Date" to a value which the c# application can interpret as "ticks"?
>>
>
> First you should use a more common DB schema instead of this proprietary
> one.

What would be a better format for the dates?

We have found that using a real date field in sql server 2005 gives odd
rounding issues - eg dates which are very close to midnight (eg 1 ms before
midnight) are rounded up to the next day. We don't want this behaviour, so
the c# application was programmed to use the ticks value (where no rounding
up to the next day occurs),

Using a formatted string for the date makes it harder to select a range of
dates (this is very easy with a numeric value).

What other/better possibilities are there?



Thanks,
Peter

From: Lothar Kimmeringer on 2 Mar 2010 06:16
Peter K wrote:

> Now I am writing a java application, which collects data and writes it to
> the database for the c# application to read. So how do I convert a java
> "Date" to a value which the c# application can interpret as "ticks"?

Assuming that "ticks" are using NT Time, GIYF giving you e.g.
http://support.citrix.com/article/CTX109645

[...]
How to convert Windows NT Time to UNIX Time:
Divide by 10,000,000 and subtract 11,644,473,600.
How to convert UNIX Time to Windows NT Time:
Add 11,644,473,600 and multiply by 10,000,000.
[...]


Regards, Lothar
--
Lothar Kimmeringer E-Mail: spamfang(a)kimmeringer.de
PGP-encrypted mails preferred (Key-ID: 0x8BC3CD81)

Always remember: The answer is forty-two, there can only be wrong
questions!
From: Lew on 2 Mar 2010 11:15
Frank Langelage wrote:
> java.util.Date has a constructor public Date(long date) with date as the
> number of milliseconds since January 1, 1970, 00:00:00 GMT.
> So this should be no problem for a programmer to solve this now.

Given that the Java type to match databases is java.sql.Timestamp, and that
has a resolution of one nanosecond, it's potentially a better choice.

--
Lew
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