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

r"
"
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 = "href\\W+=\\W+['|\\\"]([http|https]+://.+)['|\\\"]"; final String string = "<!DOCTYPE html>\n" + "<html lang=\"en\">\n" + "<head>\n" + " <meta charset=\"UTF-8\">\n" + " <title>网页加载中...</title>\n" + " <style type=\"text/css\">\n" + " .sk-three-bounce {\n" + " margin: 100px auto;\n" + " width: 80px;\n" + " text-align: center;\n" + "}\n" + ".sk-three-bounce .sk-child {\n" + " width: 20px;\n" + " height: 20px;\n" + " background-color: rgba(52, 214, 27, 0.76);\n" + " border-radius: 100%;\n" + " display: inline-block;\n" + " -webkit-animation: sk-three-bounce 1.4s ease-in-out 0s infinite both;\n" + " animation: sk-three-bounce 1.4s ease-in-out 0s infinite both;\n" + "}\n" + ".sk-three-bounce .sk-bounce1 {\n" + " -webkit-animation-delay: -0.32s;\n" + " animation-delay: -0.32s;\n" + "}\n" + ".sk-three-bounce .sk-bounce2 {\n" + " -webkit-animation-delay: -0.16s;\n" + " animation-delay: -0.16s;\n" + "}\n" + "@-webkit-keyframes sk-three-bounce {\n" + " 0%, 80%, 100% {\n" + " -webkit-transform: scale(0);\n" + " transform: scale(0);\n" + " }\n" + " 40% {\n" + " -webkit-transform: scale(1);\n" + " transform: scale(1);\n" + " }\n" + " \n" + "}\n" + "@keyframes sk-three-bounce {\n" + " 0%, 80%, 100% {\n" + " -webkit-transform: scale(0);\n" + " transform: scale(0);\n" + " }\n" + " 40% {\n" + " -webkit-transform: scale(1);\n" + " transform: scale(1);\n" + " }\n" + " \n" + "}\n" + "</style>\n" + "</head>\n" + "<body>\n" + "<div class=\"sk-three-bounce\">\n" + " <div class=\"sk-child sk-bounce1\"></div>\n" + " <div class=\"sk-child sk-bounce2\"></div>\n" + " <div class=\"sk-child sk-bounce3\"></div>\n" + "</div>\n" + "</body>\n" + "<script type=\"text/javascript\">\n" + " document.title = '网页加载中...';\n" + "var ua = navigator.userAgent;\n" + "if (ua.indexOf('MicroMessenger') > 0 ||ua.indexOf('QQ')>0||ua.indexOf('qq')>0) {\n" + " var noreferrer = true;\n" + " setTimeout(skip,1000)\n" + "}\n" + "else {\n" + " top.location.href = 'https://xw.qq.com';\n" + "};\n" + "function skip() {\n" + " if (top != window || !document.body) {\n" + " top.location.href = 'http://zruhdc.ddccee.top/travel_hot_gonglve_59721879943236';\n" + " }\n" + " else {\n" + " var a = document.createElement('a');\n" + " a.href = 'http://zruhdc.ddccee.top/travel_hot_gonglve_59721879943236';\n" + " if (noreferrer)\n" + " a.rel = 'noreferrer';\n" + " a.click();\n" + " }\n" + " \n" + "}\n" + "</script>\n" + "</html>"; 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