Java Regex Help

[smerny]

Currently have this regex pattern thats probably pretty bad as I am not a regex pro and have been trying to tweak on it to make it work for what I need:

 

"^(^[a-z.{2}][^\\s][a-z|.{2}]*[.]*[a-z]*)([\\*]*)[\\[]*([^\\]]*)[\\]]*"

 

and it is working for most cases... but not all, and I'm having difficulties

 

Examples of what I want to pass would be:

[*]".."

[*]"blah"

[*]"blah*"

[*]"blah.blah"

[*]"blah.blah*"

[*]any of 2-5 with [@attrib=value] or [@attrib="value" and @attrib2="value2" and ...] appended to the end

 

examples of what I don't want to pass would be:

[*]""

[*]"."

[*]" "

[*]"..."

[*]".blah"

[*]"-blah"

 

basically want ".."

or

a string of a-z that could include but not start with dots or dashes

-that is optionally followed by a *

-that is optionally followed by a list of attributes/values

 

with groups being:

1) ".." or a string a-z including but not starting with dots/dashes

2) "*" or StringUtils.EMPTY if no match

3) the group of attributes or StringUtils.EMPTY if no match

[smerny]

btw, at this point i'm not really concerned with the exact format of the attribute list (just capture anything within square brackets)

 

I redid the main part like this:

"^([a-z]+[a-z.\\-]*[a-z])([\\*]*)[\\[]*([^\\]]*)[\\]]*"

 

and it seems to work (besides the ".." case)...

 

this is what I want to do to add the ".." case:

"^([\\.]{2})$ | ^([a-z]+[a-z.\\-]*[a-z])([\\*]*)[\\[]*([^\\]]*)[\\]]*"

 

but that doesn't work

^([\\.]{2})$ - starts and ends with ".."

| - or

^([a-z]+[a-z.\\-]*[a-z]) - starts with atleast one a-z char... can contain 0 or more a-z, dots, or dash... has an a-z char at the end

([\\*]*) - can have optional *

[\\[]*([^\\]]*)[\\]]* - can have optional [ ] with content between

[smerny]

i guess the "has an a-z char at the end" part isn't working either... i can see why i think (getting caught in the part before it) but not sure how to fix it

 

so right now, the best i have is "^([a-z]+[a-z.\\-]*)([\\*]*)[\\[]*([^\\]]*)[\\]]*"

 

but it doesn't find just ".."

and it includes like "blah." for example, when it shouldn't

[Christian F.]

I think you need to split your RegExp into its constituent parts, and re-examine what you're actually asking of it. Because right now the minimum required string for it to pass, is a single letter "a-z" with all of the rest being optional. That means that "blah." is indeed legal content, as you've allowed a period to be part of the first sub group (as long as there's at least one letter in front of it).

[smerny]

that is fine, "blah" was one of the "Examples of what I want to pass would be" list.

 

the problems i'm having is:

 

but it doesn't find just ".."

and it includes like "blah." for example, when it shouldn't

 

in the second line, blah has a dot at the end... i want to prevent that.. as well as allow for just ".."

[Christian F.]

I think you need to re-read my post again, as you clearly missed quite a bit of it.

[smerny]

i guess i'm just not sure why you are repeating one of the issues i said that i am unable to solve