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
Processing...

Test String

Substitution
Processing...

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<!--\\[[^\\]]*(?:](?!-->)[^\\]]*)*]-->\\R?"; final String string = "<link rel=File-List href=\"filelist.xml\">\n" + "<!--[if gte mso 9]><xml>\n" + " <o:DocumentProperties>\n" + " <o:Revision>3</o:Revision>\n" + " <o:TotalTime>1</o:TotalTime>\n" + " <o:Created>2014-02-14T21:30:00Z</o:Created>\n" + " <o:LastSaved>2014-02-14T21:35:00Z</o:LastSaved>\n" + " <o:Pages>1</o:Pages>\n" + " <o:Words>58</o:Words>\n" + " <o:Characters>331</o:Characters>\n" + " <o:Lines>2</o:Lines>\n" + " <o:Paragraphs>1</o:Paragraphs>\n" + " <o:CharactersWithSpaces>388</o:CharactersWithSpaces>\n" + " <o:Version>15.00</o:Version>\n" + " </o:DocumentProperties>\n" + " <o:OfficeDocumentSettings>\n" + " <o:AllowPNG/>\n" + " </o:OfficeDocumentSettings>\n" + "</xml><![endif]-->\n" + "<link rel=themeData href=\"themedata.tx\">"; final String subst = ""; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceFirst(subst); System.out.println("Substitution result: " + result); } }

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