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 = "(\\{color[^\\}]*\\})|(\\![^!]*(thumbnail)\\!)|(^\\|[\\ \\h]*)|(\\|[\\ ]*(?=[\\n\\r]))"; final String string = "\"#### ![](https://secure.spiria.com/jira-staging/secure/viewavatar?size=xsmall&avatarId=12555&avatarType=issuetype) [MAINT-170 &nbsp;&nbsp;&nbsp; Setup a virtual IOS Development Environment](https://secure.spiria.com/jira-staging/browse/MAINT-170)####\n" + " **Description** \n" + "| |\n" + "| |\n" + "| |\n" + "|!https://www.pagerduty.com/wp-content/uploads/2016/05/pagerduty-logo-green.png!|[{color:#999999}shutterstock.pagerduty.com{color}|https://shutterstock.pagerduty.com/incidents]|\n" + "| |\n" + "| |\n" + "|Hello Don Ramsey, you have one open incident assigned to you:|\n" + " \n" + "|{color:#767676}Incident #149053{color}|\n" + "| |\n" + "|[CRITICAL: 'check_renewal_tracking' on 'prod-worker16.ma01.bigstockcorp.net'|https://shutterstock.pagerduty.com/incidents/P4HX6H1]|\n" + "| |\n" + "|[{color:#333333}View Incident{color}|https://shutterstock.pagerduty.com/incidents/P4HX6H1]|\n" + "| |\n" + "|{color:#767676}Details{color}|\n" + "|pd_nagios_object: service CONTACTPAGER: 5bb546134cb64acb845ebdf05fc3ae6b|\n" + "| |\n" + "|{color:#767676}Status{color}|\n" + "|{color:#fc0f03}Triggered{color}|\n" + "| |\n" + "|{color:#767676}Urgency{color}|\n" + "|↑ High|\n" + "| |\n" + "|{color:#767676}Assigned To{color}|\n" + "|[{color:#005c9c}Don Ramsey{color}|https://shutterstock.pagerduty.com/users/PAHPTR7]|\n" + "| |\n" + "|{color:#767676}Opened On{color}|\n" + "|[{color:#000000}Oct 24, 2017 at 11:03 AM (Eastern Time (US & Canada)) {color}\\|]|\n" + "| |\n" + "|{color:#767676}Service{color}|\n" + "|[{color:#005c9c}nagios (Bigstock){color}|https://shutterstock.pagerduty.com/services/PVF3TQU]|\n" + "| |\n" + "|{color:#767676}Escalation Policy{color}|\n" + "|[{color:#005c9c}Bigstock Team Escalation{color}|https://shutterstock.pagerduty.com/escalation_policies#PYK0IBT]|\n" + "| |\n" + "| |\n" + "|You can disable these messages (or turn off HTML emails) by adjusting [{color:#005c9c}your notification rules{color}|https://shutterstock.pagerduty.com/users/PAHPTR7].|\n" + "| | |\n" + "| |\n" + "|{color:#767676}PagerDuty, Inc., 600 Townsend St., #200, San Francisco, California, 94103 Copyright © 2008 — 2017 PagerDuty, Inc. All rights reserved.{color}|\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