RFR 8013252: Regex Matcher .start and .end should be accessible by group name

Mandy Chung mandy.chung at oracle.com
Tue Apr 30 19:43:14 UTC 2013

Hi Sherman,

Looks okay in general.  A couple of comments:

Have you considered providing a method to map from group name to its 
group index?  Would that be useful?

group(String) can simply return group(getMatchedGroupIndex(name)) rather 
than duplicating the implementation.  Similarly for start(String) and 
end(String).  Is the performance overhead due to the extra check for 
(first < 0) and (group < 0 || group > groupCount()) the concern?  I

btw, start(int) and end(int) are missing the check if (group < 0).

Nit: <tt>-1</tt> can be replaced with {@code -1}.


On 4/29/13 1:56 PM, Xueming Shen wrote:
> Hi,
> The regex named capturing group support was added into jdk7 [1].
> Matcher.group(gname) is the only direct access method we added back then
> to access the matched result. The proposed change here is to add a 
> pair of
> accessing/convenient method Matcher.start/end(gname) to access the 
> start/end
> offset info of the matched result, to match the corresponding 
> start/end/group
> (int index) access methods.
> http://cr.openjdk.java.net/~sherman/8013252/webrev
> Thanks!
> -Sherman
> [1] http://cr.openjdk.java.net/~sherman/6350801/webrev.02/

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