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How to create multiple groups in a regex?

From the string I need a group of source i.e before TO and target i.e after TO. With that I need sub group from source i.e (3:8) in a single regex pattern.
MOVE A (3:8) TO B.

It's difficult to guess what might be desired here, I'd say maybe an expression similar to:
([^(]+(\(.+?\)))\s*TO\s*(.*)
Demo
Test
import java.util.regex.Matcher;
import java.util.regex.Pattern;
final String regex = "([^(]+(\\(.+?\\)))\\s*TO\\s*(.*)";
final String string = "MOVE A (3:8) TO B\n";
final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE);
final Matcher matcher = pattern.matcher(string);
while (matcher.find()) {
System.out.println("Full match: " + matcher.group(0));
for (int i = 1; i <= matcher.groupCount(); i++) {
System.out.println("Group " + i + ": " + matcher.group(i));
}
}

Split encrypted text within brackets in java

I have encrypted text wraped with brackets, i'm trying to get only the text [|kXS6k~R5I~Q5gHR&f3gzJ[X] -->|kXS6k~R5I~Q5gHR&f3gzJ[X
Found this pattern [\[\](){}] , it works but split until first brackets or if there are parenthesesit will split the text untill them .
thanks

You can try this: "\[(.*?)\]". And don't forget to have the backslash escaped in your string otherwise it will give you error
String string = "[AA{R7QHQ8onQ~QXR7UXQzM\e{J6Y]";
String regex = "\\[(.*?)\\]";
String string = "[AA{R7QHQ8onQ~QXR7UXQzM\\e{J6Y]";
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(string);
while (matcher.find()) {
System.out.println("Full match: " + matcher.group(0));
for (int i = 1; i <= matcher.groupCount(); i++) {
System.out.println("Group " + i + ": " + matcher.group(i));
}
}

A regular expression to match zero or one occurrence of a word in Java

I have written a regex to match following pattern:
Any characters followed by hyphen followed by number followed by space followed by an optional case insensitive keyword followed by space followed by any char.
E.g.,
TXT-234 #comment anychars
TXT-234 anychars
The regular expression I have written is as follows:
(?<issueKey>^((\\s*[a-zA-Z]+-\\d+)\\s+)+)((?i)?<keyWord>#comment)?\\s+(?<comment>.*)
But the above doesn't capture the zero occurrence of '#comment', even though I have specified the '?' for the regular expression. The case 2 in the above example always fails and the case 1 succeeds.
What am I doing wrong?

#comment won't match #keyword. That is why you don't have a match try. This one it should work:
([a-zA-Z]*-\\d*\\s(((?i)#comment|#transition|#keyword)+\\s)?[a-zA-Z]*)

This may help;
String str = "1. TXT-234 #comment anychars";
String str2 = "2. TXT-234 anychars";
String str3 = "3. TXT-2a34 anychars";
String str4 = "4. TXT.234 anychars";
Pattern pattern = Pattern.compile("([a-zA-Z]*-\\d*\\s(#[a-zA-Z]+\\s)?[a-zA-Z]*)");
Matcher m = pattern.matcher(str);
if (m.find()) {
System.out.println("Found value: " + m.group(0));
System.out.println("Found value: " + m.group(1));
System.out.println("Found value: " + m.group(2));
}
m = pattern.matcher(str2);
if (m.find()) {
System.out.println("Found value: " + m.group(0));
}
m = pattern.matcher(str3);
if (m.find()) {
System.out.println("Found value: " + m.group(0));
} else {
System.out.println("str3 not match");
}
m = pattern.matcher(str4);
if (m.find()) {
System.out.println("Found value: " + m.group(0));
} else {
System.out.println("str4 not match");
}

Split with multiple special characters: √(A&B)

I have √(A&B)=|C| equation,
after split, I get this value
[√, (, A&B, ),=,|, C,|]
how can get value like this
[√(, A&B, ),=,|, C,|]
This my code,
return teks.split(""
+ "((?<=\\ )|(?=\\ ))|"
+ "((?<=\\!)|(?=\\!))|"
+ "((?<=\\√\\()|(?=\\√\\())|" //this is my problem
+ "((?<=\\√)|(?=\\√))|" //and this
+ "((?<=\\∛)|(?=\\∛))|"
+ "((?<=\\/)|(?=\\|))"
+ "((?<=\\&)|(?=\\&))"
+ "");
}

Try Matcher.find() for following regexp:
String s = "√(A&B)=|C|";
Matcher m = Pattern.compile("("
+ "(√\\()"
+ "|(\\))"
+ "|(\\w(\\&\\w)*)"
+ "|(=)"
+ "|(\\|)"
+ ")").matcher(s);
ArrayList<String> r = new ArrayList<>();
while(m.find())
r.add(m.group(1));
System.out.printf("%s", r.toString());
Result:
[√(, A&B, ), =, |, C, |]
Upd.
Or, if any symbol before parenthesis (except of "=") should be counted as one symbol with that "(":
String s = "√(A&(B&C))=(|C| & (! D))";
Matcher m = Pattern.compile("("
+ "[^\\s=]?\\(" // capture opening bracket with modifier (if any)
// you can replace it with "[√]?\\(", if only
// "√" symbol should go in conjunction with brace
+ "|\\)" // capture closing bracket
+ "|\\w" // capture identifiers
+ "|[=!\\&\\|]" // capture symbols "=", "!", "&" and "|"
+ ")").matcher(s.replaceAll("\\s", ""));
ArrayList<String> r = new ArrayList<>();
while(m.find())
r.add(m.group(1));
System.out.printf("%s -> %s\n", s, r.toString().replaceAll(", ", ",")); // ArrayList joins it's elements with ", ", so, removing extra space
Result:
√(A&(B&C))=(|C| & (! D)) -> [√(,A,&(,B,&,C,),),=,(,|,C,|,&(,!,D,),)]

RegEx in java to replace a String

I've been trying to replace this mathematical function x^2*sqrt(x^3) to this pow(x,2)*Math.sqrt(pow(x,3))
so this is the regex
/([0-9a-zA-Z\.\(\)]*)^([0-9a-zA-Z\.\(\)]*)/ pow(\1,\2)
it works in ruby, but I can't find a way to do it in java, I tried this method
String function= "x^2*sqrt(x^3)";
Pattern p = Pattern.compile("([a-z0-9]*)^([a-z0-9]*)");
Matcher m = p.matcher(function);
String out = function;
if(m.find())
{
System.out.println("GRUPO 0:" + m.group(0));
System.out.println("GRUPO 1:" + m.group(1));
out = m.replaceFirst("pow(" + m.group(0) + ", " + m.group(1) + ')');
}
String funcformat = out;
funcformat = funcformat.replaceAll("sqrt\\(([^)]*)\\)", "Math.sqrt($1)");
System.out.println("Return Value :"+ funcion );
System.out.print("Return Value :"+ funcformat );
But still doesn´t work, the output is: pow(x, )^2*Math.sqrt(x^3) as I said before it should be pow(x,2)*Math.sqrt(pow(x,3)).
Thank you!!

As others have commented, regex is not the way to go. You should use a parser. But if you want some quick and dirty:
From Matcher:
Capturing groups are indexed from left to right, starting at one.
Group zero denotes the entire pattern, so the expression m.group(0)
is equivalent to m.group().
So you need to use m.group(1) and m.group(2). And escape the caret ^ in your regex.
import java.util.regex.*;
public class Replace {
public static void main(String[] args) {
String function= "x^2*sqrt(3x)";
Pattern p = Pattern.compile("([a-z0-9]*)\\^([0-9]*)");
Matcher m = p.matcher(function);
String out = function;
if (m.find()) {
System.out.println("GRUPO 0:" + m.group(1));
System.out.println("GRUPO 1:" + m.group(2));
out = m.replaceFirst("pow(" + m.group(1) + ", " + m.group(2) + ')');
}
String funcformat = out;
funcformat = funcformat.replaceAll("sqrt\\(([a-z0-9]*)\\^([0-9]*)]*\\)", "Math.sqrt(pow($1, $2))");
System.out.println("Return Value :"+ function );
System.out.print("Return Value :"+ funcformat );
}
}