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

Substitution

Processing...

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 = "(\\r?\\n)\\s*(?=\\r?\\n)(?=[^\\s]+?|$)"; final String string = "var массив = [\n\n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n\n" + "function(){\n\n" + "var слой = document.createElement(\"div\")\n" + "слой.id = \"ID\"\n" + "document.body.appendChild(слой)\n" + "слой.style.width = \"200px\"\n" + "слой.style.height = \"200px\"\n" + "слой.style.position = \"absolute\"\n" + "слой.style.left = \"0%\"\n" + "слой.style.top = \"0%\"\n" + "слой.style.filter = \"drop-shadow(1px 1px 5px Yellow)\"\n" + "слой.style.boxShadow = \"1px 1px 5px IndianRed\"\n\n\n" + "return 1000},\n\n" + "function(){\n" + "элемент = ID\n" + "элемент.style.transition = \"all 1s cubic-bezier(0.5,-0.5,0.5,1.5) \"\n" + "элемент.style.position = \"absolute\"\n" + "элемент.style.left = \"33%\"\n" + "элемент.style.top = \"33%\"\n\n" + "return 1000},\n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n\n\n" + "]"; final String subst = "$1"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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