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I want to use below expression in my program but i don't know what do this regular expression!
please help me.
"(?=(?!^)[,;.:])|(?<=[,;.:])"
in the above expression (?=(?!^)[,;.:]) find any character set that end with [.;,:] or no? what do this (?!^) in this expression?
and this expression find any character set that end with [,;.:] or no?
please help me.
The expression matches 0-length strings that satisfy one of these two conditions:
Ahead of it is one of ,;.:, but not for 0-length strings just before the beginning of the subject string (position 0). So the subject string "." has no match at position 0, only at position 1 because of the following alternative. This is done with positive lookahead (?=) and negative lookahead (?!).
Behind it is one of ,;.:. This is done with positive lookbehind (?<=).
For instance for "aaa,1", you have two matches: at position three (after the last a, because it's followed by ,) and at position 4 (because it's preceded by ,).
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So I need to check if a word is a pattern of alternating vowel and cosonant (Or consonant and vowel) in Java.
I want to make it a regex but I just came with this incomplete regex expression:
[aeiouAEIOI][^aeiouAEIOI]
Any ideas?
Thanks :)
Update: It's not regex restricted, so it can be an option if anyone has any ideas
One way is using a lookahead to check if neither two vowels nor two consonants next to each other.
(?i)^(?!.*?(?:[aeiou]{2}|[^aeiou]{2}))[a-z]+$
See this demo at regex101 (used i flag for caseless matching, the \n in demo is for staying in line)
Update: Thank you for the comment #Thefourthbird. For matching at least two characters you will need to change the last quantifier: Use [a-z]{2,} (two or more) instead of [a-z]+ (one or more). For only matching an even amount of characters (2,4,6,8...), change this part to: (?:[a-z]{2})+
FYI: If you use this with matches you can drop the ^ start and $ end anchor (see this Java demo).
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I'm working on a regex for getting a specific number pattern from the URL string.
Requirements: Desire string should start from - or /, followed by a sequence of digits and ending with a / or nothing.
I tried: [-\/](\d+)(\/|$), but for e.g. in www.abc.com/pages/Toms-1777/14623420046 I want /14623420046(i.e. the second occurring digit sequence), but according to my regex, the result will be -1777/. I was trying negative lookbehind but not able to make any progress. I'm new to all this. Please guide.
Test cases: (with matched pattern)
www.abc.com/pages/Essen-Massage-Therapy-LLC/130561253629638
www.abc.com/biz/finn-mccools-santa-monica-2
www.abc.com/summerset.gardens.7
www.abc.com/pages/Toms-1777/14623420046
www.abc.com/pages/The-Clean-Masters/1403753595526512
www.abc.com/24hfsheepsheadbay
www.abc.com/sample2NVCoolSpace
www.abc.com/pages/Jet-Set-3920/542495615847409
www.abc.com/temp.buildings.77
www.abc.com/2423423453534temp/2312312312312312312
www.abc.com/Ptemp-Gtemp-Dtemp-189398324428792/temp
You want that $ in either case. Instead of 'slash OR end', it's more 'optional slash and then a very much not-optional end'. So.. /?$. You don't need to normally escape slashes, especially in java regexes:
Pattern.compile("[-/](\\d+)/?$")
This reads: From minus or slash, a bunch of digits, then 0 or 1 slashes, then the end. Note, use find() and not matches() - matches only works if the entire string matches, which it won't, as the - or / occurs halfway through.
EDIT: Was missing a backslash in the java string.
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I have function call like BeanUtils.copyProperties(source, destination);
I want to change it to BeanUtils.copyProperties(destination, source); in many places. How to do it using Regex? What is the regex command to do this?
I'm using eclipse to do find and replace.
Search for (with regex setting turned on)
BeanUtils\.copyProperties\s*\(\s*([\w\_]+)\s*\,\s*([\w\_]+)\s*\)\s*\;
And replace with:
BeanUtils.copyProperties($2, $1);
First escape all literal characters with backslash \
Wherever a space can be found when writing code, match it with 0 or more spaces. That by using \s* Could use [ ]* but \s might be sufficient in this case.
Then add captures for the source and destination by adding them in brackets. Or use [\w\_]+ to match other variable names. With a + to mean at least 1 char. NB: if your variable have any other non-alphanumeric chars, add them to the [...] list.
Finally in the replace, switch the captures.
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I am confuse in the logic behind the code (?<=\\D)(?=\\d)|(?<=\\d)(?=\\D)")
it is separating numbers and alphabets like input String abc12dc23 then it is spliting it as output abc 12 dc 23.
I just want the explanation how the above code is working?
This regex:
(?<=\D)(?=\d)|(?<=\d)(?=\D)
matches 2 kinds of patterns, as suggested by the | character:
This pattern:
(?<=\D)(?=\d)
and this pattern:
(?<=\d)(?=\D)
The former looks for a position in the string where there is a non-digit (\D) character before that position and a digit (\d) after it. The latter looks for a position where the reverse happens, a digit before and a non-digit after.
To say this in a more abstract way, the regex is looking for digit-non-digit boundaries.
The split method looks for all occurrences of the pattern and splits the string when it finds one.
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This is very basic but can't seem to find a answer when searching.
I have a string that's in the format:
[[[0.093493,51.6037],[0.091015,51.5956],[0.088596,51.5857]]]
The doubles inside the brackets are [latitude coordinate,longitude coordinate].
From this I'd like to extract the coordinates.
What should I put inside the search pattern if I use a Pattern/Matcher solution?
Assume that format with brackets is always correct but the doubles can vary in length.
Basicly what I want the code to do is:
Find "[" left of a number, then find this "," and return what's in between
AND another searchpattern that:
find "," and "]" and return what's inbetween.
Keep it simple by using this regex:
\[(\d+\.\d+),(\d+\.\d+)\]
and repeat the matcher.find() till all matches are found.
You matches are in group #1 and group #2
RegEx Demo