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 = "^([[:alpha:]]+\\s)+((V2)\\s-\\s).*$"; final String string = "AppMessages - Dev\n" + "AppMessages - Master\n" + "AppMessages2 - Dev\n" + "AppMessages2 - Master\n" + "AWS - Octopus Release\n" + "BellHop - Dev\n" + "BellHop - Master\n" + "Bellhop Model - Dev\n" + "Bellhop Model - Master\n" + "Bellhop Model V2 - Dev\n" + "Bellhop Model V2 - Master\n" + "BellHop Services - Dev\n" + "BellHop Services - Master\n" + "BSG Log4j Extras - Dev\n" + "BSG Log4j Extras - Master\n" + "BSG Log4j Extras V2- Dev\n" + "BSG Log4j Extras V2- Master\n" + "BSG-BOM - Dev\n" + "BSG-BOM - Master\n" + "BSG-BOM2 - Dev\n" + "BSG-BOM2 - Master\n" + "Core Model - Dev\n" + "Core Model - Master\n" + "Core Model V2 - Master\n" + "Core Model V2- Dev\n" + "Core Services - Dev\n" + "Core Services - Master\n" + "Core Services V2 - Dev\n" + "Core Services V2 - Master\n" + "DealerLocator - Dev\n" + "EMS Services - Dev\n" + "EMS Services - Master\n" + "EMS Services V2 - Dev\n" + "EMS Services V2 - Master\n" + "Entitlements Services - Dev\n" + "Entitlements Services - Master\n" + "Entitlements SOAP API - Dev\n" + "Laipac Service - Master\n" + "Laipac Services - Dev\n" + "Laipac Services V2 - Dev\n" + "Laipac Services V2 - Master\n" + "LDK Services - Dev\n" + "LDK Services - Master\n" + "LDK Services V2 - Dev\n" + "LDK Services V2 - Master\n" + "LicenseAdmin - Dev\n" + "LicenseAdmin - Master\n" + "LiteFlexNetIntegration - Dev\n" + "LiteFlexNetIntegration - Master\n" + "LiteIntegration - Dev\n" + "LiteIntegration - Master\n" + "LiteLib - Dev\n" + "LiteLib - Master\n" + "Logviewer - Dev\n" + "Logviewer - Master\n" + "Messaging Services - Dev\n" + "Messaging Services - Master\n" + "OptionKeys - Dev\n" + "OptionKeys - Master\n" + "OptionKeysAPI - Dev\n" + "OptionKeysAPI - Master\n" + "Pools API - Dev\n" + "Pools API - Master\n" + "Pools Model - Dev\n" + "Pools Model - Master\n" + "Pools Model V2 - Dev\n" + "Pools Model V2 - Master\n" + "Pools Services - Dev\n" + "Pools Services - Master\n" + "Pools Services V2 - Dev\n" + "Pools Services V2 - Master\n" + "SubscriptionManager - Dev\n" + "SubscriptionManager - Master\n" + "SubscriptionManager2 - Dev\n" + "SubscriptionManager2 - Master\n" + "Tid Services - Dev\n" + "Tid Services - Master\n" + "TidHTTP - Dev\n" + "TidHTTP - Master\n" + "Upload templates to S3 - branch2Dev\n" + "Upload templates to S3 - Dev\n" + "Upload templates to S3 - Master\n" + "Upload templates to S3 - Test\n" + "VirtualWarehouse - Dev\n" + "VirtualWarehouse - Master\n" + "VirtualWarehouse Services - Dev\n" + "VirtualWarehouse Services - Master\n" + "VirtualWarehouse Services V2 - Dev\n" + "VirtualWarehouse Services V2 - Master\n" + "VW Axiom - Dev\n" + "VW Axiom - Master\n" + "VW Lite API - Dev\n" + "VW Lite API - Master\n" + "VW Remedy Events - Dev\n" + "VW Remedy Events - Master\n" + "VW Remedy Events Consumer - Dev\n" + "VW Remedy Events Consumer - Master\n" + "VW Remedy Events Lib - Dev\n" + "VW Remedy Events Lib - Master\n" + "VW Scheduled Tasks - Dev\n" + "VW Scheduled Tasks - Master\n" + "VW Sentinel - Dev\n" + "VW Sentinel - Master\n" + "VW Subscriptions - Dev\n" + "VW Subscriptions - Master\n" + "VW5 - Dev\n" + "VW5 - Master\n" + "WooCommerce API - Dev\n" + "WooCommerce API - Master\n" + "WooCommerce Model - Dev\n" + "WooCommerce Model - Master\n" + "WooCommerce Model V2 - Dev\n" + "WooCommerce Model V2 - Master\n" + "WooCommerce Services - Dev\n" + "WooCommerce Services - Master\n" + "WooCommerce Services V2 - Dev\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