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

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 = "^[0-9a-zA-Z]{10}.*([A-Z\\s]{16,})\\\\n"; final String string = "\n\n\n" + "4nXQOweFyC\\x10HWANG SEAN SOJIN\\n\n" + "^[0-9a-zA-Z]{10}\\\\[0-9a-z]{3}([A-Z\\s]{3,})\\\\n\n\n" + "^[0-9a-zA-Z]{10}\\\\x10([A-Z\\s]{3,})\\\\n\n\n" + "^[0-9a-zA-Z]{10}\\\\x14([A-Z\\s]{3,})\\n\n\n" + "# 정의되어야 함\n\n" + "4nYBfE4dug\\x07GUO JIE\\n\n\n" + "4nYWf22CBO\\x08LI FULAN\\n\n\n\n" + "^[0-9a-zA-Z]{10}\\\\x08([A-Z\\s]{3,})\\\\n\n\n\n" + "4mfP1jNaF4\\x14광진실리콘(주)\\n\n\n\n" + "4nXckRULYB\\x0fCHANG LAI HSIEN\\n\n\n" + "0UN97Wa9oU\\t507030360A0130(\\x010\\x011\\x011\\x010\\x0202\\x011(\\x010(\\x010\\x01N\\x0b20년/20년\\x082021031860860\\x012\\x011\\x03B\\x011\\x01N\\x0820210318\\x0820210318\\x0820210318\\x132021-03-18 12:01:34\\x011\\x0fCHANG LAI HSIEN\\x132021-03-18 10:57:01\\x132021-03-18 10:57:14\\x02[메리츠화재] 모바일 전자서명 안내\\n\n\n" + "4nAjfKqh8i\\x0bQUAN CANXIE\\n\n\n" + "^[0-9a-zA-Z]{10}\\x0b(\\([가-힣].*)\\n\n" + "^[0-9a-zA-Z]{10}([A-Z가-힣\\s]{2,})\\\\n\n\n\n\n" + "4nXzVRFyIl\\tJIN GUANGMAN\\n\n\n\n" + "4nXzVRFyIl\\t김현수\\n\n\n" + "4nJcIVZHxD\\x0b(주)철마\\n\n" + "^[0-9a-zA-Z]{10}\\\\x0b(\\\\([가-힣].*)\\\\n\n" + "^[0-9a-zA-Z]{10}\\\\x0b(\\([가-힣].*)\\\\n\n\n\n\n\n" + "^[0-9a-zA-Z]{10}\\t([A-Z가-힣\\s]{2,})\\n\n\n\n\n" + "^[0-9a-zA-Z]{10}\\\\t([A-Z가-힣\\s]{2,})\\\\n\n\n" + "^[0-9a-zA-Z]{10}\\t([A-Z가-힣\\s]{2,})\\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