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
Processing...

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 = "<(\\S+) tag=\"([^\"]+)\">([^<]+)<\\/(?1)>"; final String string = "<image tag=\"plan\">http://img.nmarket.pro/photo/pid/E2087273-BDC1-4717-9F2E-20F6A76E0479/?v=1&amp;cid=2415&amp;pid=E2087273-BDC1-4717-9F2E-20F6A76E0479&amp;wpsid=51&amp;hash=031b3173e71427e3673247f8a80135c8</image>\n" + " <image tag=\"houseuncategorized\">http://img.nmarket.pro/photo/pid/1C372F09-3440-49FE-9A6D-048EF51B5F73/?v=1&amp;cid=2415&amp;pid=1C372F09-3440-49FE-9A6D-048EF51B5F73&amp;wpsid=51&amp;hash=810aea88a716dfff20ae5c182bf38888</image>\n" + " <image tag=\"houseuncategorized\">http://img.nmarket.pro/photo/pid/3628BB57-3D4C-43A9-AD00-843E5D5F657F/?v=1&amp;cid=2415&amp;pid=3628BB57-3D4C-43A9-AD00-843E5D5F657F&amp;wpsid=51&amp;hash=abf93d04775994f55fe82eb84dfad54e</image>\n" + " <image tag=\"houseuncategorized\">http://img.nmarket.pro/photo/pid/3EDBD70B-7393-4A93-9BAD-54B32DA49EEF/?v=1&amp;cid=2415&amp;pid=3EDBD70B-7393-4A93-9BAD-54B32DA49EEF&amp;wpsid=51&amp;hash=0565037ec9d45e15d0c84df34100e3dc</image>\n" + " <image tag=\"houseuncategorized\">http://img.nmarket.pro/photo/pid/2C8FE09E-AE07-4E13-89F0-B4695A7428AF/?v=1&amp;cid=2415&amp;pid=2C8FE09E-AE07-4E13-89F0-B4695A7428AF&amp;wpsid=51&amp;hash=f1a03336866c285fb16a604708a9c15e</image>\n" + " <image tag=\"housemain\">http://img.nmarket.pro/photo/pid/0CCFA7EA-3757-4740-A721-BF75DEAAB11C/?v=1&amp;cid=2415&amp;pid=0CCFA7EA-3757-4740-A721-BF75DEAAB11C&amp;wpsid=51&amp;hash=c69a5cf80cd48f6ccc4b68c077d5f301</image>\n" + " <image tag=\"complexscheme\">http://img.nmarket.pro/photo/pid/29E51673-697F-4F38-9F9B-1DF28B22F3A1/?v=1&amp;cid=2415&amp;pid=29E51673-697F-4F38-9F9B-1DF28B22F3A1&amp;wpsid=51&amp;hash=c826f221b1d372d0defbc04c857f01f3</image>\n" + " <image tag=\"floorplan\">http://img.nmarket.pro/photo/pid/F0DB967A-895F-4740-9FFE-FF3F100519EE/?v=1&amp;cid=2415&amp;pid=F0DB967A-895F-4740-9FFE-FF3F100519EE&amp;wpsid=51&amp;hash=15c82a24c7c0c6bacd8b1551c44ca0ec</image>\n" + "<parking tag=\"hello\">world</class>\n" + " "; final String subst = "<$1><$2>$3</$2></$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