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

r"
"
mg

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 = "^\\W|^\\d|^[A-Z ]+$|^[tT]able.+|^[Ff]igure.+|^[fF][aA][Xx].+|^[Ee]mail.+|^EMAIL.+|\\.[\\w]+\\.|\\d[\\+\\-\\\\\\*\\/]\\d|[\\(\\)\\+\\-\\\\\\*\\/] [\\(\\)\\+\\-\\\\\\*\\/]"; final String string = "AL SJ \n" + "alias56 45 5\n" + "23 \n\n" + "table 3\n" + "I love my mom (YES)\n" + "(123)\n\n" + "EMAIL\n" + "email :\n" + "Fig.2.3.\n" + "a.b.b.\n\n" + "Model ES2/50/600 ALD Vacuum Technology will be operated in December 2007\n\n" + "International Price Ex) \\1,000,000\n\n" + "(1985) An almost ideal demand system for visitor expenditures, Journal of Transport Economics and Policy, Vol.19, No.2, 161-171\n\n\n" + "Then he gave advice to Morgenstern not to pay too much respect to the Austrian tradition and to go on with his own belief of the impossibility of forecasting\n\n" + "Head Office & Plant: 3-20, 1-chome, Higashisuna, Koto-ku, Tokyo 136-0074\n\n" + "micro-amanlysis of ther fh ehif wnf . ejf-e weew e$ kgejg ^%&%^ ekjwe843759843 iy3ty dfgmdbkjjkdg73 dg gh\n\n" + "This study applies the Repeated Discrete Choice Model (hereafter RDC) as one of (.\n\n" + "."; final Pattern pattern = Pattern.compile(regex, 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