RE: Slow processing

Is there any time to use Regular Expressions 
when the format of the steam doesn't change?

In other words, if I already know the format, 
why use Regular Expressions?  

I've added Regular Expression when the 
format of a text file can change.  For 
instances, a generic log system that can 
read any text log file.

- Malcolm

  >-----Original Message-----
  >From: Daniel F. Savarese [mailto:[email protected]]
  >Sent: Saturday, April 27, 2002 7:17 PM
  >To: ORO Users List
  >Subject: Re: Slow processing 
  >
  >
  >
  >In message 
  ><[email protected]
  >>, "Robert Edgar" w
  >rites:
  >>which has got me up to about 450 line a second 
  >but that is still slow though
  >>I am stil using the readline, but using 
  >readline and a string tokenizer I
  >>can get 10x this speed which seem to me to 
  >indicate that the readline is not
  >>really a bottleneck but that the regex still is 
  >or is regex not really
  >>designed for this sort of processing and I 
  >would be better just doing a
  >>simple hard coded parse of the string?.
  >
  >You'll definitely do better than you are now by 
  >reading the entire input
  >into a char array, but now that you bring it up, 
  >yes, in general, any
  >tokenization or parsing task that can be done in 
  >an application-specific
  >manner without regular expressions will be a 
  >good bit faster than with
  >regular expressions (and this is far more true 
  >with the performance
  >enhancements in JDK 1.4).  Right now you're 
  >probably paying a good deal
  >of overhead related to the saved groups.  If I 
  >had been paying more
  >attention I would have noticed what you were 
  >doing and suggested just
  >using StreamTokenizer (I usually suggest that 
  >people avoid using regular
  >expressions when they don't need them).  Anyway, 
  >it's kind of like when
  >people use Util.substitute() when 
  >StringBuffer.replace() will do.  Although
  >now that there's a String.replace() and split() 
  >supporting regular
  >expression in JDK 1.4 ... but that would be 
  >going off topic.
  >
  >daniel
  >
  >
  >
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