How to extract matches from (\d+[hms])+ ?

Guy Steele guy.steele at
Thu Sep 25 05:06:35 UTC 2014

(A lurker sticking his nose in here! :-)  Is it your intent also to match "30s1h" or "20m30m" as a time duration?

If not, you might be better off with a pattern such as "((\\d+)h)?((\\d+)m)?((\\d+)s)?" and then the whole problem caused by the outer "+" iteration disappear (but you may need to check whether the original string was empty).

But maybe that takes all the fun out of it.

--Guy Steele

On Sep 25, 2014, at 12:51 AM, Wang Weijun < at> wrote:

> Hi Sherman
> I want to match a time duration like "1h20m30s" and "2h". It looks like if I directly use the pattern "((\\d+)([hms]))+", group(2) and group (3) only return the last match (i.e. 30 and s for 1h20m30s). So I tried multiple matching with "(\\d)([hms])" only, but find() does not always match from the beginning, and lookingAt() does not advance after one call.
> This is my code now;
> int start = 0;
> while (true) {
>  if (!m.find() || m.start() != start) {
>    throw new Exception();
>  }
>  start = m.end();
>  print(,;
>  if (m.hitEnd()) break;
> }
> print("Done");
> Is this the correct way?
> Thanks
> Max

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