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how to check regex starts and ends with regex

I am having the regex for capturing string if they are in between double quote and not start or end with /.
But the regex solution which I wanted.
The regex should not capture
Condition 1. Capture text between two double or single quotes.
Condition 2. But it shouldn't capture if starts with [ and ends with ]
Condition 3. But it shouldn't if starts with /" and ends with /' or starts with /" and ends with /'
Example:
REGEX: \"(\/?.)*?\"
Input: Functions.getJsonPath(Functions.getJsonPath(Functions.getJsonPath(Functions.unescapeJson("test"), "m2m:cin.as"),"payloads_ul.test"),"[/"Dimming Value/"]",input["test"]["in"])
output:
captured output:
1. "test"
2. "m2m:cin.as"
3. "payloads_ul.test"
4. [/"Dimming Value/"]
5. "test"
6. "in"
Expected result:
1. "test"
2. "m2m:cin.as"
3. "payloads_ul.test"
4. [/"Dimming Value/"]
Condition 1 explanation:
Capture the text between double or single quotes.
example:
input : "test","m2m:cin.as"
output: "test","m2m:cin.as"
Condition 2 explanation:
If the regex is between starts with [ and ends with ] but it is having double or single quote then also it should not capture.
example:
input: ["test"]
output: it should not capture
Condition 3 explanation:
In the above-expected result for the input "[/"Dimming Value/"]" there is a two-time double quote but is capturing only one excluding /". So, the output is [/"Dimming Value/"]. Like this, I want if /' (single quote preceded by /).
Note:
For input "[/"Dimming Value/"]" or '[/'Dimming Value/']', here although the text is between double quote and single quote and having [ and ] it should not ignore the string. The output should be [/"Dimming Value/"].

As I understood, you want to capture text between double quotes, except:
if initial double quotes prefixed by [ or final double quotes suffixed by ]
doubles quotes prefixed by / should not be the begin or end of matched text
I don't know if you want also capture text between single quotes, because you text is not complete clear.
For create a non capture group with negative matching of prefixed chars, you need a group of type Negative Lookbehind, with syntax (?<!prefix that you dont want), but this is not present on java or javascript regex engine.
The best regex that I build to return what you want for you example (but only work on PHP or python (you can check it on site regex101.com or similar)) is:
(?<![\[/])\"(?!\])(\/?.)*?\"(?![\]/])
I added the restriction for don't match if initial double quotes suffixed by ] to prevent match "][" on text ["test"]["in"]
Anyway, this will not solve your problem, since will not work within java or javascript engine!
Do you have any way to process the results, and exclude the bad matches?
If so, you can match bad prefix and bad suffix and exclude it from the results:
[\[]?\"(\/?.)*?\"[\]]?
this will return:
"test"
"m2m:cin.as"
"payloads_ul.test"
"[/"Dimming Value/"]"
["test"]
["in"]
Full javascript code, including pos processing:
'Functions.getJsonPath(Functions.getJsonPath(Functions.getJsonPath(Functions.unescapeJson("test"), "m2m:cin.as"),"payloads_ul.test"),"[/"Dimming Value/"]",input["test"]["in"])'
.match(/[\[]?\"(\/?.)*?\"[\]]?/g).filter(s => !s.startsWith('[') && !s.endsWith(']'))
this will return:
"test"
"m2m:cin.as"
"payloads_ul.test"
"[/"Dimming Value/"]"
EDIT:
equivalent java code:
CharSequence yourStringHere = "Functions.getJsonPath(Functions.getJsonPath(Functions.getJsonPath(Functions.unescapeJson(\"test\"), \"m2m:cin.as\"),\"payloads_ul.test\"),\"[/\"Dimming Value/\"]\",input[\"test\"][\"in\"])";
Matcher m = Pattern.compile("[\\[]?\\\"(\\/?.)*?\\\"[\\]]?")
.matcher(yourStringHere);
while (m.find()) {
String s = m.group();
if (!s.startsWith("[") && !s.endsWith("]")) {
allMatches.add(s);
}
}

Extraction of subsequences that end with point and space by regular expression

hy
I want to extract sub sentences of this sentence by regular expression:
it learn od fg network layout. kdsjhuu ddkm networ.12kfdf. learndfefe layout. learn sdffsfsfs. sddsd learn fefe.
I couldn't write a correct regular expression for Pattern.compile.
This is my expression:([^(\\.\\s)]*)([^.]*\\.)
Actually, i need a way for writing "read everthing except \\.\\s
sub sentences:
it learn od fg network layout.
kdsjhuu ddkm networ.12kfdf.
learndfefe layout.
learn sdffsfsfs.
sddsd learn fefe.

Just split your string with regex "\\. "
String[] arr= str.split("\\. ");

You can use this pattern with the find method:
Pattern p = Pattern.compile("[^\\s.][^.]*(?:\\.(?!\\s|\\z)[^.]*)*\\.?");
Matcher m = p.matcher(yourText);
while(m.find()) {
System.out.println(m.group(0));
}
Pattern details:
[^\\s.] # all that is not a whitespace (to trim) or a dot
[^.]* # all that is not a dot (zero or more times)
(?: # open a non-capturing group
\\. (?!\\s|\\z) # dot not followed by a whitespace or the end of the string
[^.]* #
)* # close and repeat the group as needed
\\.? # an optional dot (allow to match a sentence at the end
# of the string even if there is no dot)

How to remove comma after a word pattern in java

Please help me out to get the specific regex to remove comma after a word pattern in java.
Assume, I would like to delete comma after each pattern where the pattern is <Word$TAG>, <Word$TAG>, <Word$TAG>, <Word$TAG>, <Word$TAG> now I want my output to be <Word$TAG> <Word$TAG> <Word$TAG> <Word$TAG> . if I used .replaceAll(), it will replace all commas, but in my <Word$TAG> Word may have a comma(,).
For example, Input.txt is as follows
mms§NNP_ACRON, site§N_NN, pe§PSP, ,,,,,§RD_PUNC, link§N_NN, ....§RD_PUNC, CID§NNP_ACRON, team§N_NN, :)§E
and Output.txt
mms§NNP_ACRON site§N_NN pe§PSP ,,,,,§RD_PUNC link§N_NN ....§RD_PUNC CID§NNP_ACRON team§N_NN :)§E

You could use ", " as search and replace it with " " (space) as below:
one.replace(", ", " ");
If you think, you have "myString, ,,," or multiple spaces in between, then you could use replace all with regex like
one.replaceAll(",\\s+", " ");

(?<=[^,\s]),
Try this.Replace by empty string.See demo.
http://regex101.com/r/lZ5mN8/5

Match the data you want, not the one you don't want.
You probably want ([^ ]+), and keep the bracketed data, separated by whitespace.
You might even want to narrow it down to ([^ ]+§[^ ]+),. Usually, stricter is better.

You could use a positive lookahead assertion to match all the commas which are followed by a space or end of the line anchor.
String s = "mms§NNP_ACRON, site§N_NN, pe§PSP, ,,,,,§RD_PUNC, link§N_NN, ....§RD_PUNC, CID§NNP_ACRON, team§N_NN, :)§E";
System.out.println(s.replaceAll(",(?=\\s|$)",""));
Output:
mms§NNP_ACRON site§N_NN pe§PSP ,,,,,§RD_PUNC link§N_NN ....§RD_PUNC CID§NNP_ACRON team§N_NN :)§E

Java regex: need one regex to match all the formats specified

A log file has these pattern appearing more than once in a line.
for example the file may look like
dsads utc-hour_of_year:2013-07-30T17 jdshkdsjhf utc-week_of_year:2013-W31 dskjdskf
utc-week_of_year:2013-W31 dskdsld fdsfd
dshdskhkds utc-month_of_year:2013-07 gfdkjlkdf
I want to replace all date specific info with "Y"
I tried :
replaceAll("_year:.*\s", "_year:Y ");` but it removes everything that occurs after the first replacement,due to greedy match of .*
dsads utc-hour_of_year:Y
utc-week_of_year:Y
dshdskhkds utc-month_of_year:Y
but the expected result is:
dsads utc-hour_of_year:Y jdshkdsjhf utc-week_of_year:Y dskjdskf
utc-week_of_year:Y dskdsld fdsfd
dshdskhkds utc-month_of_year:Y gfdkjlkdf

Try using a reluctant quantifier: _year:.*?\s.
.replaceAll("_year:.*?\\s", "_year:Y ")
System.out
.println("utc-hour_of_year:2013-07-30T17 dsfsdgfsgf utc-week_of_year:2013-W31 dsfsdgfsdgf"
.replaceAll("_year:.*?\\s", "_year:Y "));
utc-hour_of_year:Y dsfsdgfsgf utc-week_of_year:Y dsfsdgfsdgf

I am not sure what you are really trying to do and this answer is only based on your example. In case you want to do something else leave comment below or edit your question with more specific information/example
It removes everything after _year: because you are using .*\\s which means
.* zero or more of any characters (beside new line),
\\s and space after it
so in sentence
utc-hour_of_year:2013-07-30T17 dsfsdgfsgf utc-week_of_year:2013-W31 dsfsdgfsdgf
it will match
utc-hour_of_year:2013-07-30T17 dsfsdgfsgf utc-week_of_year:2013-W31 dsfsdgfsdgf
// ^from here to here^
because by default * quantifier is greedy. To make it reluctant you need to add ? after * so try maybe
"_year:.*?\\s"
or even better instead .*? match only non-space characters using \\S which is the same as negation of \\s that can be written as [^\\s]. Also if your data can be at the end of your input you shouldn't probably add \\s at the end of your regex and space in your replacement, so try maybe one of this ways
.replaceAll("_year:\\S*", "_year:Y")
.replaceAll("_year:\\S*\\s", "_year:Y ")

How to split this string using Java Regular Expressions

I want to split the string
String fields = "name[Employee Name], employeeno[Employee No], dob[Date of Birth], joindate[Date of Joining]";
to
name
employeeno
dob
joindate
I wrote the following java code for this but it is printing only name other matches are not printing.
String fields = "name[Employee Name], employeeno[Employee No], dob[Date of Birth], joindate[Date of Joining]";
Pattern pattern = Pattern.compile("\\[.+\\]+?,?\\s*" );
String[] split = pattern.split(fields);
for (String string : split) {
System.out.println(string);
}
What am I doing wrong here?
Thank you

This part:
\\[.+\\]
matches the first [, the .+ then gobbles up the entire string (if no line breaks are in the string) and then the \\] will match the last ].
You need to make the .+ reluctant by placing a ? after it:
Pattern pattern = Pattern.compile("\\[.+?\\]+?,?\\s*");
And shouldn't \\]+? just be \\] ?

The error is that you are matching greedily. You can change it to a non-greedy match:
Pattern.compile("\\[.+?\\],?\\s*")
^

There's an online regular expression tester at http://gskinner.com/RegExr/?2sa45 that will help you a lot when you try to understand regular expressions and how they are applied to a given input.

WOuld it be better to use Negated Character Classes to match the square brackets? \[(\w+\s)+\w+[^\]]\]
You could also see a good example how does using a negated character class work internally (without backtracking)?