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

/
/
g

Test String

Substitution

Processing...

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 = "values '\\K[^']*"; final String string = "create database link ODSPUSH.CISCO.COM connect to XXDM identified by values '056D98F3367CAC4478383FFB673E4D22329E172F2B25778BE3' using 'TS3ODS'; \n\n" + "conn GESADM/abcd123 \n" + "create database link TS3CFN.CISCO.COM connect to GESADM identified by values '05A0E92F39E91BA002F98DE9A46FC72B31572483E12D3AAB67' using 'TS3CFN'; \n\n\n" + "create database link SYNSTG.CISCO.COM connect to SYN_CLNTSRV identified by values '066C10B37E3A3D0A3AA96B9FDE063585B662E3921F3C3F5A3E224BD4394A7BD659DAD174ABDE36594E7F3B466D6B0DCF78F13D75BA3B47090D295\n" + "8F8604E637462A2A41F74458E0C0EB649EE9A537AD2AE109A20B2DA09E5F9A28D666B8980651B79C0E76BBD6CBBCD169645970FDD615291C8557DBC79F527BF32E14A845025' using 'SYNSTG'; "; final String subst = ""; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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