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

/
/
g

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 = "(\\d{1}[[:punct:]]\\s*\\[){1}(.*\\s*\\{)(.*\\s*\\])"; final String string = "1.\n\n" + "[Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam mauris lectus, lobortis vitae semper vitae, molestie in tellus. Etiam fermentum quam quis posuere pharetra. Morbi id erat id ante consequat tincidunt. Ut et lorem hendrerit, euismod tortor ac, blandit ligula. In fermentum, tellus quis dignissim interdum, ante mi malesuada turpis, rutrum maximus sem magna vel ante. Etiam maximus lacinia augue nec scelerisque. Aliquam euismod lectus ante, eget fringilla sem pretium ac. Sed eu ex tempor, eleifend dolor nec, semper sem...\n\n" + "{B:rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1}{W:L5_lectus ante}\n\n" + "]\n\n" + "2.\n\n" + "[Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam mauris lectus,\n\n" + "Lobortis vitae semper vitae, molestie in tellus. Etiam fermentum quam quis posuere pharetra.\n\n" + "Morbi id erat id ante consequat tincidunt.\n\n" + "{B:rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1}{S:e2e4}{D:1000}{S:e7e6}{D:5000}{S:d2d4}{S:d7d5}{D:1000}{S:b1c3}{S:1000}{A:Tc3e4}{D:3000}{R}{S:g8f6}{D:1000}{S:e4e5}{D:1000}{S:f6d7}{W:L5_G1_C110}{W:L5_G1_C001}{W:L5_G1_C002}{W:L5_G1_C003}{W:L5_G1_C004}\n\n" + "]\n\n" + "3.\n\n" + "[Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam mauris lectus, lobortis vitae semper vitae, molestie in tellus.\n\n" + "Etiam fermentum quam quis posuere pharetra. Morbi id erat id ante consequat tincidunt.\n\n" + "Ut et lorem hendrerit, euismod tortor ac, blandit ligula. In fermentum, tellus quis dignissim interdum, ante mi malesuada turpis, rutrum maximus sem magna vel ante. Etiam maximus lacinia augue nec scelerisque. Aliquam euismod lectus ante, eget fringilla sem pretium ac.\n\n" + "Sed eu ex tempor, eleifend dolor nec, semper sem...\n\n" + "{B:rnbqkb1r/pppn1ppp/4p3/3pP3/3P4/2N5/PPP2PPP/R1BQKBNR w KQkq - 0 1}{D:5000}{G:BPc7}{S:c7c5}{D:2000}{S:c5c7}{X:c7}{P:BPc7}{D:3000}{S:f2f4}{D:5000}{S:c7c5}{D:4000}{S:d4c5}{D:1000}{S:b8c6}{W:L5_G1_C005}{W:L5_G1_C006}{W:L5_G1_C007}\n\n" + "]\n\n" + "4.\n\n" + "[Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam mauris lectus, lobortis vitae semper vitae, molestie in tellus. Etiam fermentum quam quis posuere pharetra. Morbi id erat id ante consequat tincidunt. Ut et lorem hendrerit, euismod tortor ac, blandit ligula. In fermentum, tellus quis dignissim interdum, ante mi malesuada turpis, rutrum maximus sem magna vel ante. Etiam maximus lacinia augue nec scelerisque. Aliquam euismod lectus ante, eget fringilla sem pretium ac. Sed eu ex tempor, eleifend dolor nec, semper sem...\n\n" + "{B:r1bqkb1r/pp1n1ppp/2n1p3/2PpP3/5P2/2N5/PPP3PP/R1BQKBNR w KQkq - 0 1}{D:1500}{S:a2a3}{D:9000}{A:Ta3b4}{D:2000}{R}{A:Wb2b4}{D:3000}{R}{S:f8c5}{W:L5_G1_C008}\n\n" + "]\n\n" + "5.\n\n" + "[Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam mauris lectus, lobortis vitae semper vitae, molestie in tellus.\n\n" + "Etiam fermentum quam quis posuere pharetra. Morbi id erat id ante consequat tincidunt. Ut et lorem hendrerit, euismod tortor ac, blandit ligula. In fermentum, tellus quis dignissim interdum, ante mi malesuada turpis, rutrum maximus sem magna vel ante. Etiam maximus lacinia augue nec scelerisque.\n\n" + "Aliquam euismod lectus ante, eget fringilla sem pretium ac. Sed eu ex tempor, eleifend dolor nec, semper sem...\n\n" + "{B:r1bqk2r/pp1n1ppp/2n1p3/2bpP3/5P2/P1N5/1PP3PP/R1BQKBNR w KQkq - 0 1}{D:3000}{S:d1g4}{D:2000}{A:Dg4g7}{H:g7}{D:5000}{R}{C}{D:3000}{S:g7g6}{D:10000}{S:g1f3}{D:2500}{S:a7a6}{D:2000}{A:Bb7b5}{D:4000}{R}{S:f1d3}{D:2000}{S:b7b5}{W:L5_G1_C009}{W:L5_G1_C010}{W:L5_G1_C011}{W:L5_G1_C012}{W:L5_G1_C013}{W:L5_G1_C014}\n\n" + "]"; final Pattern pattern = Pattern.compile(regex); 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