Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gim

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(([(|\\[](?P<series>[^)\\]]*)[)|\\]]))?((?P<author>.*[^\\s][^\\-])[\\s]+-[\\s]*)?(?P<title>[^(]*)([(|\\[](?:[\\s]*(?P<published>(([12][\\d]{3,3})(?:(?!([^.\\)\\-a-zA-Z_]*(-+[^.\\)a-zA-Z_]+)+)))))?)?[\\s]*([,]?[\\s]*(?P<publisher>[\\s\\w\\s]*)[\\s]*)?([,]?[\\s]*(isbn:|isbn[-]?13:)?(?P<isbn>[0-9-]+))?[)|\\]])?"; final String string = "(1958, Open Road d34234234, 978-1-4532-1730-6).epub\n" + "(1958, Open Ro234ad , 9781-4532-o1730-6).epub\n" + "(1958, Open Rosd234ad ).epub\n" + "( 1958 ).epub\n" + "(1958).epub\n" + "( Open Road ).epub\n" + "(Open road , 9234-1-4532-17300-9-6).epub\n" + "(1234, 9234-1-4532-17300-9-6).epub\n" + "(91886).epub\n" + "(9186).epub\n" + "(1186).epub\n\n" + "title (1958, Open Road34234234, 978-1-4532-1730-6).epub\n" + "(asdf) author, a2 - title ioiuoi-uyoiu (1958, Open Ro234ad , 9781-4532-1730-6).epub\n" + "author, adf - title ioiuoi-uyoiu (1958, Open Rosd234ad ).epub\n" + "author, adf - title ioiuoi-uyoiu ( 1958 ).epub\n" + "author, adf - title ioiuoi-uyoiu (1958).epub\n" + "author, adf - title ioiuoi-uyoiu ( Open Road ).epub\n" + "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu (Open road , 9234-1-4532-17300-9-6).epub\n" + "author, adf - title ioiuoi-uyoiu (1234, 9234-1-4532-17300-9-6).epub\n" + "author, adf - title ioiuoi-uyoiu (1234, 923416).epub\n" + "author, adf - title ioiuoi-uyoiu ( 91886-8).epub\n" + "author, adf - title ioiuoi-uyoiu ( 9186 ).epub\n" + "author, adf - title ioiuoi-uyoiu ( 1186 ).epub\n" + "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , isbn:9234-1-4532-17300-9-6).epub\n" + "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , isbn13:9234-1-4532-17300-9-6).epub\n" + "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , isbn-13:9234-1-4532-17300-9-6).epub\n" + "(dddfasdfasdf) author666, a66df - title ioiuoi-uyoiu ( Open road , 9234-1-4532-17300-9-6).epub"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE); 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)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html