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

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 = "^\n" + "(?<batch_number>\\d{2})-\n" + "(?:\n" + " (?<component>QQ|CO|CG)\n" + " (?<target_group>[AS])\n" + " (?<paper>P)?\n" + ")\n" + "(?:-\n" + " (?<domain>(?:LDW|MAT|REA|SCI|XYZ)\n" + " (?<division>[abc])?\n" + " )\n" + ")?\n" + "-(?<authoring_point>[TN])\n" + "$"; final String string = "01-COS-SCIa-N\n" + "02-COS-SCIb-N\n" + "03-COS-SCIc-N\n" + "04-QQS-N\n" + "05-QQA-N\n" + "06-COS-LDW-N\n" + "07-COS-XYZ-N\n" + "08-CGA-SCI-N\n" + "11-COS-MATa-T\n" + "12-COS-MATb-T\n" + "13-COS-REAa-T\n" + "14-COS-REAb-T\n" + "15-COS-SCIa-T\n" + "16-COS-SCIb-T\n" + "17-CGA-SCI-T\n" + "18-CGA-MAT-T\n" + "19-CGA-REA-T\n" + "21-COSP-REAa-T\n" + "22-COSP-REAb-T\n" + "23-COSP-MATa-T\n" + "24-COSP-MATb-T\n" + "25-COSP-SCIa-N\n" + "26-COSP-SCIa-T\n" + "27-QQSP-N\n" + "28-QQAP-N\n" + "29-COSP-XYZ-N\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.COMMENTS); 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