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

/
/
gm

Test String

Substitution

Processing...

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 = "(>.*?)\\QStyle\\E([^=][^<]*)"; final String string = "<div><p style=\"text-align:left;\">Style: <span style=\"float:right;\">Casual</span></p></div><div><p style=\"text-align:left;\">Color: <span style=\"float:right;\">Navy Blue</span></p></div><div><p style=\"text-align:left;\">Pattern Type: <span style=\"float:right;\">Plain</span></p></div><div><p style=\"text-align:left;\">Neckline: <span style=\"float:right;\">Round Neck</span></p></div><div><p style=\"text-align:left;\">Length: <span style=\"float:right;\">Long</span></p></div><div><p style=\"text-align:left;\">Type: <span style=\"float:right;\">A Line</span></p></div><div><p style=\"text-align:left;\">Details: <span style=\"float:right;\">Pearls</span></p></div><div><p style=\"text-align:left;\">Details: <span style=\"float:right;\">Frill</span></p></div><div><p style=\"text-align:left;\">Details: <span style=\"float:right;\">Beaded</span></p></div><div><p style=\"text-align:left;\">Details: <span style=\"float:right;\">Pocket</span></p></div><div><p style=\"text-align:left;\">Sleeve Length: <span style=\"float:right;\">Half Sleeve</span></p></div><div><p style=\"text-align:left;\">Season: <span style=\"float:right;\">Spring/Fall</span></p></div><div><p style=\"text-align:left;\">Composition: <span style=\"float:right;\">75% Cotton</span></p></div><div><p style=\"text-align:left;\">Composition: <span style=\"float:right;\">Denim</span></p></div><div><p style=\"text-align:left;\">Composition: <span style=\"float:right;\">25% Polyester</span></p></div><div><p style=\"text-align:left;\">Fabric: <span style=\"float:right;\">Non-Stretch</span></p></div><div><p style=\"text-align:left;\">Waist Line: <span style=\"float:right;\">Natural</span></p></div><br /><table border=\"1\"><thead><tr><th>size</th><th>Shoulder </th><th>Bust </th><th>Waist Size </th><th>Hip Size </th><th>Sleeve Length </th><th>Length </th><th>Bicep Length </th><th>Cuff </th></tr></thead><tbody><tr><td>XS</td><td> 38 cm</td><td> 91 cm</td><td> 90 cm</td><td> 101 cm</td><td> 39 cm</td><td> 139 cm</td><td> 30 cm</td><td> 25 cm</td></tr><tr><td>S</td><td> 39 cm</td><td> 95 cm</td><td> 94 cm</td><td> 105 cm</td><td> 40 cm</td><td> 140 cm</td><td> 31 cm</td><td> 26 cm</td></tr><tr><td>M</td><td> 40 cm</td><td> 99 cm</td><td> 98 cm</td><td> 109 cm</td><td> 41 cm</td><td> 141 cm</td><td> 32 cm</td><td> 27 cm</td></tr><tr><td>L</td><td> 41 cm</td><td> 103 cm</td><td> 102 cm</td><td> 113 cm</td><td> 42 cm</td><td> 142 cm</td><td> 33 cm</td><td> 28 cm</td></tr></tbody></table>"; final String subst = "$1MODIFIED_COLOR$2"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(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