How to extract a substring using regex

Question

I have a string that has two single quotes in it, the ' character. In between the single quotes is the data I want.

How can I write a regex to extract "the data i want" from the following text?

mydata = "some string with 'the data i want' inside";

Answer 1

String dataIWant = mydata.split("'")[1];

See Live Demo

Answer 2

as in javascript:

mydata.match(/'([^']+)'/)[1]

the actual regexp is: /'([^']+)'/

if you use the non greedy modifier (as per another post) it's like this:

mydata.match(/'(.*?)'/)[1]

it is cleaner.

Answer 3

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Test {
    public static void main(String[] args) {
        Pattern pattern = Pattern.compile(".*'([^']*)'.*");
        String mydata = "some string with 'the data i want' inside";

        Matcher matcher = pattern.matcher(mydata);
        if(matcher.matches()) {
            System.out.println(matcher.group(1));
        }

    }
}

Answer 4

In Scala,

val ticks = "'([^']*)'".r

ticks findFirstIn mydata match {
    case Some(ticks(inside)) => println(inside)
    case _ => println("nothing")
}

for (ticks(inside) <- ticks findAllIn mydata) println(inside) // multiple matches

val Some(ticks(inside)) = ticks findFirstIn mydata // may throw exception

val ticks = ".*'([^']*)'.*".r    
val ticks(inside) = mydata // safe, shorter, only gets the first set of ticks

Answer 5

Because you also ticked Scala, a solution without regex which easily deals with multiple quoted strings:

val text = "some string with 'the data i want' inside 'and even more data'"
text.split("'").zipWithIndex.filter(_._2 % 2 != 0).map(_._1)

res: Array[java.lang.String] = Array(the data i want, and even more data)

Answer 6

You don't need regex for this.

Add apache commons lang to your project (http://commons.apache.org/proper/commons-lang/), then use:

String dataYouWant = StringUtils.substringBetween(mydata, "'");