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 = ".*@softcomputer\\.com>? *(?:\"? *<\\S+> *)?$"; final String string = "== Real scc\n" + "Mary Bills <marybil@softcomputer.com>\n" + " <ellie@softcomputer.com>\n" + " <thereasaw@softcomputer.com>\n" + "test@softcomputer.com\n" + "<test@softcomputer.com>\n" + "olexiyry@softcomputer.com <olexiyry@softcomputer.com>\n" + "Deseriee Harkins <deseriee@softcomputer.com>\n\n" + "== Forged scc\n" + "Dorota Mazurek <dorotam@softcomputer.com> <reservations@nesthotel.com>\n" + "Nikki Taft <nicolet@softcomputer.com> <Muhammad.owais@abtach.com>\n" + "Lynette Didia <ldidia@softcomputer.com> <Muhammad.owais@abtach.com>\n" + "Dorota Mazurek <dorotam@softcomputer.com> <centralbookings@kbcsa.co.za>\n" + "Jeffrey Marr <jeffreym@softcomputer.com> <srvadv5.blr@vw-ppsmotors.co.in> \n" + "Iryna Dmytriyeva @SCC <idmy@softcomputer.com> <sc@grupoinrexsa.com>\n" + "Vickie Nix vickieh@softcomputer.com <m.recovery@albarondebt.com>\n" + "Bill Young <billyo@softcomputer.com> <sara@eaurenaissance.com>\n\n" + "== Questionable\n" + "\"Kurt Veith <kurtv@softcomputer.com>\" <marlene.robles@mld.com.mx>\n" + "\"softcomputer.com\" <MAIL.QUOTA@servers.com>\n" + "\"marksm@softcomputer.com\" <mark560sl@gmail.com>\n\n" + "== Valid non-forged addresses\n" + "\"sarahze@softcomputer.com via Smartsheet\" <user@smartsheet.com>\n" + "\"yuvi softcomputer.com\" <hugginshospital.notification@zixmessagecenter.com>\n" + "<technicalsupport@softcomputer.com.au>\n" + "\"Secure Email From yevgeny@softcomputer.com via Message Pickup Center\" <emx-intermedia@securemail.intermedia.net>\n" + "\"Secure Email From yevgeny@softcomputer.com via Message Pickup Center\" <emx-intermedia@securemail.intermedia.net>\n" + "\"mpettis@softcomputer.com via SurveyMonkey\" <member@surveymonkeyuser.com>"; 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