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

@"
"
gxmn

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 = "\\[\\[(\n" + " # link, and optional anchor\n" + " (?<link>[^\\|\\#\\]]+)?(\\#(?<anchor>[^\\|\\]]+))? \n" + " # display title (optional)\n" + " (\\|(?<title>[^|\\]]+))? \n" + " # tooltip (optional)\n" + " (\\|(?<tooltip>[^|\\]]+))? \n" + ")\\]\\]"; final String string = "# Entry\n\n" + "## Definition\n" + "A published announcement made by a trusted [[Emitter]], detailing an event that occurred on their platform. \n\n\n" + "## Specifications (3.0)\n" + "#v3_0 \n\n" + "A trustlist entry follows a basic structure, with parts being omitted during ingest, as these are filled by the receiving [[Directory]], responsible for the good tenure of this entry, and its correlation to existing data.\n\n" + "As SocialGuard 1.0 to 3.0 tied its data to the [Discord](https://discord.com) [[Platform]], all data types are bound to that end.\n\n" + "| Property | Type | Description | Requirement |\n" + "| -------- | ---- | ----------- | ----------- |\n" + "| `id` | Guid | ID of the entry. | Set by API |\n" + "| `userId` | UInt64 | ID of the receiving [[User]]. | Required |\n" + "| `entryAt` | DateTime | Date/Time at which the entry was emitted on the [[Directory]]. | Set by API |\n" + "| `lastEscalated` | DateTime | Date/Time at which the entry was last escalated/edited. | Set by API |\n" + "| `emitterId` | String | ID of the [[Emitter]] responsible for this Entry. | Set by API |\n" + "| `emitter` | [[Emitter#Specifications (3.0)]] | Details of the [[Emitter]] responsible for this entry. | Set by API |\n" + "| `escalationLevel` | [[#Range: Escalation level (3.0)]] | Escalation/Severity level of the events indicated by this entry. | Required |\n" + "| `escalationNote` | String | Details of the event that led to this entry. | Required |\n\n" + "### Range: Escalation level (3.0)\n" + "This range defines the severity of an event leading to an entry. It is ranged by severity level and ordered from lowest to highest severity :\n\n" + "1. **Suspicious**\n" + " The [[User]] is marked as suspicious. Their behaviour should be monitored.\n" + "2. **Untrusted**\n" + " The [[User]] is marked as untrusted. It is advised to exercise caution when interacting with them.\n" + "3. **Blacklisted**\n" + " The [[User]] is deemed dangerous. Banning this user is greatly advised.\n\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS | 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