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

/
/
igm

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 = "(?<FULL>^(?<PATH>(?:\\/|\\.|\\.\\.){0,2})(?<CAPTURE1>\\/[^\\/\\s]+)?(?<CAPTURE2>\\/[^\\/\\s]+)?(?<CAPTURE3>\\/[^\\/\\s]+)?(?<CAPTURE4>\\/[^\\/\\s]+)?(?<CAPTURE5>\\/[^\\/\\s]+)?(?<CAPTURE6>\\/[^\\/\\s]+)?(?<FILENAME>\\/[^\\/\\s]+)$)"; final String string = "./src/index.js\n\n" + "./src/index.js#Soda\n\n" + "./src/index.js?soda=fries\n" + "./src/index.js#soda?fries=hamburger\n" + "./src/index.js#soda?fries=hamburger&bag+o=chips\n" + "http://www.google.com/blugh/hello\n" + "https://www.google.com:8080/src/ui/template-management/create-template/versioning/version.js\n" + "http://localhost:8080/blugh/hello\n" + "../MyPath\n" + "This here is a normal sentence, though!\n" + "./src/ui/{FILE}.js[x]?\n" + "./src/ui/login.js\n" + "./src/ui/logout.js\n\n" + "./src/ui/{FILE}/{FILE}.js[x]?\n" + "./src/ui/ad-hoc-messages/ad-hoc-messages.js\n" + "./src/ui/editor/editor.jsx\n" + "./src/ui/select-interaction/select-interaction.jsx\n" + "./src/ui/template-management/template-management.js\n\n" + "./src/ui/{DIR}/{FILE}/{FILE}.js[x]?\n" + "./src/ui/ad-hoc-messages/send-ad-hoc-message/send-ad-hoc-message.js\n" + "./src/ui/admin-console/Department-management/Department-management.js\n" + "./src/ui/admin-console/tag-management/tag-management.js\n" + "./src/ui/template-management/create-template/create-template.js\n" + "./src/ui/template-management/create-template/versioning/version.js\n\n" + "./src/ui/{DIR}/{FILE}.js[x]?\n" + "./src/ui/shared/select-template-to-send.js\n" + " \n" + "/select-interaction\n" + "/template-management\n" + "/template-management/create-template\n" + "/template-management/edit-template\n" + "/ad-hoc-messages\n" + "/ad-hoc-messages/send-ad-hoc-mail\n" + "/admin-console/category-management\n" + "/admin-console/tag-management\n" + "/Logout"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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