I need to extract the text between the last brackets of a string. This is how it looks like:
String text= "[text1][text2][text3][text4]";
I need to get
String result = "text4"
I have tried with Regex but i can't manage to make it work. I would appreciate some help with getting the regex and the substring. Thank you very much
Use the regex, .+(\[.+\])$ and capture group(1).
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Main {
public static void main(String[] args) {
String text = "[text1][text2][text3][text4]";
Matcher matcher = Pattern.compile(".+(\\[.+\\])$").matcher(text);
if (matcher.find()) {
System.out.println(matcher.group(1));
}
}
}
Output:
[text4]
Explanation of the regex at regex101:
You don't need regex. You can use lastIndexOf
String text= "[text1][text2][text3][text4]";
System.out.println(text.substring(text.lastIndexOf("[")+1, text.lastIndexOf("]")));
I am having trouble with regex here.
Say i have this input:
608094.21.1.2014.TELE.&BIG00Z.1.1.GBP
My regex looks like this
(\d\d\d\d\.\d?\d\.\d?\d)|(\d?\d\.\d?\d\.\d?\d?\d\d)
I want to extract the date 21.1.2014 out of the string, but all i get is
8094.21.1
I think my problem here is, that 21.1.2014 starts within the (wrong) match before. Is there a simple way to make the matcher look for the next match not after the end of the match before but one character after the beginning of the match before?
You could use a regex like this:
\d{1,2}\.\d{1,2}\.\d{4}
Working demo
Or shorten it and use:
(\d{1,2}\.){2}\d{4}
If the date is always surrounded by dot:
\.(\d\d\d\d\.\d?\d\.\d?\d|\d?\d\.\d?\d\.\d?\d?\d\d)\.
I hope this will help you.
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Test {
public static void main(String[] args) {
String x = "608094.21.1.2014.TELE.&BIG00Z.1.1.GBP";
String pattern = "[0-9]{2}.[0-9]{1}.[0-9]{4}";
// Create a Pattern object
Pattern r = Pattern.compile(pattern);
// Now create matcher object.
Matcher m = r.matcher(x);
if (m.find( )) {
System.out.println("Found value: " + m.group() );
}else {
System.out.println("NO MATCH");
}
}
I am trying to find a match between commas if it contains a specific string.
so far i have ,(.*?myString.?*),
Obviously this finds all the input between the first comma in the entire input and the first comma after the string i want. How do i reference the comma immediately before the string that i want?
Edit: i also want to find the match that occurs after a specific set of characters
ie. occurs after (fooo)
dsfdsdafd,safdsa,gfdsgdtheMatchfdsgfd,dsafdsa,dsfoooafd,safdsa,gfhhhgdtheMatchfhhhfd,dsafdsa
returns gfhhhgdtheMatchfhhhfd, not gfdsgdtheMatchfdsgfd
The following regex should do it :
[^,]+theMatch.*?(?=,)
see regex demo / explanation
Java ( demo )
import java.util.regex.Matcher;
import java.util.regex.Pattern;
class RegEx {
public static void main(String[] args) {
String s = "dsfdsdafd,safdsa,gfdsgdtheMatchfdsgfd,dsafdsa";
String r = "[^,]+theMatch.*?(?=,)";
Pattern p = Pattern.compile(r);
Matcher m = p.matcher(s);
while (m.find()) {
System.out.println(m.group()); // gfdsgdtheMatchfdsgfd
}
}
}
Edit
use this regex fooo.*?([^,]+theMatch.*?)(?=,) demo
You are finding too much because .* will include the comma.
You need the following regular expression: ,([^,]*myinput[^,]*),
[^,]* basically says find all non-comma characters.
I would suggest the following code:
import java.util.regex.*;
public class Main {
public static void main(String[] args) {
String str = "dsfdsdafd,safdsa,myinput,dsafdsa";
Pattern p = Pattern.compile(",([^,]*myinput[^,]*),");
Matcher m = p.matcher(str);
if(m.find()) {
System.out.println(m.group(0));
// prints out ",myinput,"
System.out.println(m.group(1));
// prints out "myinput"
}
}
}
Here is a StackOverflow question that is basically the same with some very good answers associated:
Regex to find internal match between two characters
For more on regular expressions in Java look here: http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html
If you want the position of the comma proceeding your input string use the following code:
import java.util.regex.*;
public class Main {
public static void main(String[] args) {
String str = "dsfdsdafd,safdsa,myinput,dsafdsa";
Pattern p = Pattern.compile(",([^,]*myinput[^,]*),");
Matcher m = p.matcher(str);
if(m.find()) {
System.out.println(str.indexOf(m.group(0)));
// prints out "16"
}
}
}
By feeding the match of the regular expression into the String Method indexOf( you are able to locate the position of the start of your string.
Edit:
To find the occurrence of a string following another string, simply modify the regex to: fooo.*,([^,]*theMatch[^,]*),
fooo.* will greedily consume all characters between fooo and the start of your match.
Example code:
import java.util.regex.*;
public class Main {
public static void main(String[] args) {
String str = "dsfdsdafd,safdsa,gfdsgdtheMatchfdsgfd,dsafdsa,dsfoooafd,safdsa,gfhhhgdtheMatchfhhhfd,dsafdsa";
Pattern p = Pattern.compile("fooo.*,([^,]*theMatch[^,]*),");
Matcher m = p.matcher(str);
if(m.find()) {
System.out.println(m.group(1));
// prints out: gfhhhgdtheMatchfhhhfd
}
}
}
The usual approach is to use a pattern that cannot match your delimiter in place of .. In this case, you need that only at the front of the pattern; you can use a reluctant quantifier at the back as you already do (though you've misspelled it). For example:
,([^,]*myString.*?),
I want to replace some regex with regex in java for e.g.
Requirement:
Input: xyxyxyP
Required Output : xyzxyzxyzP
means I want to replace "(for)+\{" to "(for\{)+\{" . Is there any way to do this?
I have tried the following code
import java.util.regex.Pattern;
import java.util.regex.Matcher;
public class ReplaceDemo2 {
private static String REGEX = "(xy)+P";
private static String INPUT = "xyxyxyP";
private static String REGEXREPLACE = "(xyz)+P";
public static void main(String[] args) {
Pattern p = Pattern.compile(REGEX);
// get a matcher object
Matcher m = p.matcher(INPUT);
INPUT = m.replaceAll(REGEXREPLACE);
System.out.println(INPUT);
}
}
but the output is (xyz)+P .
You can achieve it with a \G based regex:
String s = "xyxyxyP";
String pattern = "(?:(?=xy)|(?!^)\\G)xy(?=(?:xy)*P)";
System.out.println(s.replaceAll(pattern, "$0z"));
See a regex demo and an IDEONE demo.
In short, the regex matches:
(?:(?=xy)|(?!^)\\G) - either a location followed with xy ((?=xy)) or the location after the previous successful match ((?!^)\\G)
xy - a sequence of literal characters xy but only if followed with...
(?=(?:xy)*P) - zero or more sequences of xy (due to (?:xy)*) followed with a P.
I am having a problem tring to split a sting based on parentheses.
I have a String like this
Fe(C5H5)2FeO3 and I need to split the sting in to an array so the array reads
Fe
(C5H5)2
FeO3
Im an using this code.
String form = "Fe(C5H5)2FeO3";
from.split([()]+);
I am having trouble getting the characther after the ")" to split out.
This also has to work for multiple sets of () in the same string.
Thanks
positive look ahead and look behind can do some of this:
String formula = "Fe(C5H5)2FeO3";
String regex = "(?=\\()|(?<=\\)\\d)";
String[] tokens = formula.split(regex );
System.out.println(Arrays.toString(tokens));
For more on this, check out the regular expressions tutorial
You can use a simple regex to match parts of the sequence instead of splitting on a regex:
import java.util.*;
import java.util.regex.*;
import java.lang.*;
class Main {
public static void main (String[] args) throws java.lang.Exception
{
String formula = "Fe(C5H5)2FeO3";
Pattern p = Pattern.compile("[^(]+|[(][^)]*[)]\\d+");
Matcher m = p.matcher(formula);
while (m.find()) {
System.out.println(m.group());
}
}
}
This program produces the output below:
Fe
(C5H5)2
FeO3