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 = "^2$"; final String string = "# ___ ___ ___ ___ ___ \n" + "# | _ )_ ) __| / __| __ _ _ ___ ___ _ _ | _ \\___ ___\n" + "# | _ \\/ /\\__ \\ \\__ \\/ _| '_/ -_) -_) ' \\| / -_|_-<\n" + "# |___/___|___/__|___/\\__|_| \\___\\___|_||_|_|_\\___/__/\n" + "# |_ _| __| \\/ | _ \\ | /_\\_ _| __| \n" + "# | | | _|| |\\/| | _/ |__ / _ \\| | | _| \n" + "# |_| |___|_| |_|_| |____/_/ \\_\\_| |___| \n" + "# \n" + "# PLEASE MODIFY FOR YOUR OWN USAGE\n" + "# Playfield Screen resolution width/height\n" + "1920\n" + "1080\n" + "# Backglass Screen resolution width/height\n" + "1280\n" + "1024\n" + "# Define Backglass using Display Devicename screen number (\\\\.\\DISPLAY)x or screen coordinates (@x) or screen index (=x)\n" + "2\n" + "# x position For the backglass relative To the upper left corner Of the Playfield screen\n" + "0\n" + "# y position For the backglass On the selected display (Normally left at 0)\n" + "0\n" + "# width/height Of the DMD area In pixels - For 3 screen setup\n" + "551\n" + "189\n" + "# X/Y position Of the DMD area relative To the upper left corner Of the backglass screen - For 3 screen setup\n" + "367\n" + "813\n" + "# Y-flip, flips the LED display upside down\n" + "0\n" + "# X/Y position pos When StartBackground Is active, relative To upper left corner Of Playfield ('Small' Button In the Options)\n" + "0\n" + "0\n" + "# width/height Of the backglass When StartBackground Is active\n" + "0\n" + "0\n" + "# C:\\path\\Frame (The path To the location where you have the background image)\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