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 = "\\(\\\\x07([0-9]{4,})|\\(\\\\t([0-9]{4,})\\("; final String string = "#걸려야함\n\n" + "4nYoywMzx6630636\\x010\\x0200\\x011\\x011\\x03\\x14\\x03\\x14\\x03\\x03\\x0820210430\\x0820410430\\x0820210430\\x0820410430\\x03(\\x071000000(\\x041190\\x03.\\x0202(\\x010\\x03d\\x08207504306AAAU(\\x0230\\x1e012020460104600200000000020020\\x1e01202046010460020000000002002030630636009910200201020020000999--020020------2-01--\\x03CTL\\x013(\\x010(\\x010(\\x010(\\x010(\\x010(\\x010(\\x010\\x03#NA(\\x011(\\x010(\\x010(\\x010\\x011\\x03(\\x011\\x03-\\x01 \\x03#NA\\x011\\x01 \\x011\\x0200(\\x041190(\\x010\\x03N갱신형 재진단암진단비(2년 대기형)[기본계약](계속보장형)\\x03\\x01 \\x012\\x03#NA\\x03\\x03#NA(\\x041190\\x03#NA(\\x010\\x012\\x03#NA\\x03#NA\\x010(\\x010(\\x010(\\x010(\\x010(\\x010(\\x010\\x03(\\x010\\x03\\x03\\x03\\x03(\\x010\\x0220\\x01 \\x01 (\\x010\\x03\\x01{\\x03\\x03\\x03\\n\n\n\n" + "4nYpMQSq0v620255\\x010\\x0200\\x011\\x011\\x03\\x01\\x03\\x01\\x03\\x03\\x0820210430\\x0820220430\\x0820210430\\x0820220430\\x03(\\x0850000000(\\x041320\\x03*\\x0201(\\x0215\\x03\\x08203604306AABI(\\x011\\x1c0100104223310010000000001001\\x1c0100104223310010000000001001/0620255009990009999000999000999----------2-01--\\x03CTL\\x013(\\x010\\x011(\\x010(\\x010(\\x010(\\x010(\\x010(\\x010\\x03#NA(\\x011(\\x010(\\x010(\\x010\\x011\\x03(\\x011\\x03)\\x01 \\x03#NA\\x011\\x01 \\x011\\x0200(\\x041811(\\x010\\x03\\x1f갱신형 상해입원의료비\\x03\\x03100\\x011\\x03#NA\\x03\\x03#NA(\\x041320\\x013(\\x010\\x012\\x03#NA\\x03#NA\\x011(\\x010(\\x010(\\x010(\\x010(\\x010(\\x010\\x03(\\x010\\x03\\x03\\x03\\x03(\\x010\\x0201\\x01 \\x01 (\\x010\\x03_\\x01{\\x03\\x03\\x02\\n\n\n" + "\\(\\\\x08([0-9]{4,})\\([0-9]{3,}\n\n\n\n\n\n\n\n" + "'4nXfg3E6Qb(\\x011(\\x011\\x03CTL\\x133190026942021031120\\x0201\\x040001\\n'\n\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