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Locating Data via Pattern Matching

 
Greenhorn
Posts: 26
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With reference to K and B SCJP6 page 499. I would appreciate explanation why the answer is not

Pattern is \d\w
4 56
7 7ab

why was b ommited??





% java Regex "\d\w" "ab4 56_7ab"

Produces the output

Pattern is \d\w
4 56
7 7a


Thanks
 
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The pattern is a digit character followed by a word charater -- aka. two characters. How can the match return three characters, when the pattern is only looking for two characters?

Henry
 
Ranch Hand
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look carefully there is no quantifier so it will just look for a digit followed by any character and wiil give you that pattern only but if there was a '+' quantifier for '/w' then it would have returned everything after that unless there is a space or string has ended.
 
Ida Achi
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I have no idea why I had imagined seeing a quantifier. Thanks for pointing that out.
 
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