Extract part of a string between two special characters in java

Question

String stringToSearch = "About ||PrimarySchool|| %  of children in ||Country|| attend primary school. ||SecondarySchoolFemale|| % of girls and ||SecondarySchoolMale|| % of boys finish secondary school. Literacy is ||LiteracyFemale|| % for females and ||LiteracyMale|| % for males.";

I want extra string between two special characters like ||anystring||, but it is not working. I tried to use Pattern-Matcher of Java but it is not working - it returns an empty array.

I have tried to follow Java- Extract part of a string between two special characters.

Pattern pattern = Pattern.compile("||(.*?)||");

score 1 · Answer 1 · answered May 22 '18 at 10:47

It happens because | character has a special meaning in Regex so you have to escape it using \ character. See the demo at Regex101.

Moreover, in Java, you have to escape this character with double backslash \\.

Pattern pattern = Pattern.compile("\\|\\|(.*?)\\|\\|");

score 1 · Accepted Answer · answered May 22 '18 at 10:48

You need escape |

String stringToSearch = "About ||PrimarySchool|| %  of children in ||Country|| attend primary school. ||SecondarySchoolFemale|| % of girls and ||SecondarySchoolMale|| % of boys finish secondary school. Literacy is ||LiteracyFemale|| % for females and ||LiteracyMale|| % for males.";
Pattern pattern = Pattern.compile("\\|\\|([^|]*)\\|\\|");
Matcher matcher = pattern.matcher(stringToSearch);
while (matcher.find()) {
    System.out.println(matcher.group(1));
}

Result:

PrimarySchool
Country
SecondarySchoolFemale
SecondarySchoolMale
LiteracyFemale
LiteracyMale

Extract part of a string between two special characters in java

2 Answers2