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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: regex capability
Date: Mon, 04 Apr 2011 22:13:39 +0200
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On 04.04.2011 10:26, bugbear wrote:
> Roedy Green wrote:
>> Consider a string like this:
>>
>> Support DDR2 1066/800/667/533/400 DDR2 SDRAM
>>
>> Is it possible to compose a regex that will peel out those numbers for
>> you each in its own field, or do you have to extract the string
>> "1066/800/667/533/400" and use split?
>>
>> The various things I have tried just grab the last number.
>
> I think normal practice (in Perl, and Java) would be repeated
> use of a fairly simple regexp.
>
> In Java, I use
>
> while(matcher.find()) {
> ...
> }
>
> The key is that Matcher is stateful.

And for added security a two level approach could be taken:

// untested
Pattern whole = Pattern.compile("Support DDR2 (\\d+(?:/\\d+)*) DDR2 SDRAM");

Pattern number = Patter.compile("\\d+");

Matcher m = whole.matcher(input);

if ( m.matches() ) {
   for (m = number.matcher(m.group(1)); m.find();) {
     int x = Integer.parse(m.group());
   }
}
else {
   // error?
}

Kind regards

	robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/