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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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 = "^\\\"(?<timestart>\\d{4}\\/\\d{2}\\/\\d{2}\\s\\d{2}\\:\\d{2}\\:\\d{2})?([\\\"|\\,]*)?(?<recipient>[\\w|\\.|\\-|_|\\d]*@(?<domainimpacted>[\\w|\\.|\\-|_|\\d]*))?([\\\"|\\,]*)?(?<subject>[\\w|\\s|\\#|\\@|\\±|\\§|\\d|\\!|\\$|\\%|\\^|\\,|\\.|\\(|\\)|\\[|\\]|\\{|\\}|\\:|\\-|\\&|\\*|\\'|\\=|\\+]*)?([\\\"|\\,]*)?(?<action>\\w*)?([\\\"|\\,]*)?(?<sender>[\\w|\\.|\\-|_|\\d]*@(?<domainorigin>[\\w|\\.|\\-|_|\\d]*))?([\\\"|\\,]*)?(?<account>[\\w|\\.|\\-|_|\\d|\\,|\\s]*)?([\\\"|\\,]*)?(?<status>[\\w|\\.|\\-|_|\\d]*)?([\\\"|\\,]*)?(?<object>[\\w|\\.|\\-|_|\\d]*)?([\\\"|\\,]*)?(?<reason>[\\w|\\.|\\-|_|\\d]*)?([\\\"|\\,]*)?(?<policy>[\\w|\\.|\\-|_|\\d]*)?([\\\"|\\,]*)?(?<objecttype>[\\w|\\.|\\-|_|\\d|\\s|\\,]*)?([\\\"|\\,]*)?(?<size>[\\d]*)?([\\\"|\\,]*)?(?<command>[\\w|\\.|\\-|_|\\d]*)?([\\\"|\\,]*)?(?<objectname>[\\w|\\.|\\-|_|\\d]*)?([\\\"|\\,]*)?(?<threatname>[\\w|\\.|\\-|_|\\d]*)?([\\\"|\\,]*)?"; final String string = "\"2020/04/07 08:26:21\",\"shabbir.jafri@mcb.com.pk\",\"REQUIRED ORIGINAL LC # 0054ILS200@!±026, MCB to MCB.(NOVATEX)\",\"Accepted\",\"ppta.treasury@lottechem.pk\",\"None\",\"None\",\"None\",\"Clean\",\"None\",\"Portable Document Format\",\"131835\",\"None\",\"None\",\"None\"\n" + " \n" + "\"2020/04/05 15:20:02\",\"telecom.support@mcb.com.pk\",\"MCB14005 Lhr: Gulberg Gelria - ATM Down\",\"Accepted\",\"Abbas.Zaheer@ncr.com\",\"Zaheer, Abbas\",\"Whitelisted\",\"None\",\"Spam\",\"None\",\"JPEG Interchange Format,JPEG Interchange Format,JPEG Interchange Format,JPEG Interchange Format\",\"18837\",\"None\",\"None\",\"None\"\n" + " \n" + "\"2020/04/07 08:27:02\",\"narain.das@mcb.com.pk\",\"New Doc 2020-04-07 13.25.15 - Page 1\",\"Accepted\",\"naraindas24@gmail.com\",\"Narain Das\",\"None\",\"None\",\"Clean\",\"None\",\"Portable Document Format\",\"397990\",\"None\",\"None\",\"None\""; 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