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

/
/
uxmg

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 = "(?(DEFINE)\n" + " (?<protocol> (?<=^|[^a-z]) [a-z]+? : )\n" + " (?<domain> (?:[a-z\\-]+\\.)+[a-z\\-]+ )\n" + " (?<ip> (?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?) )\n" + " (?<port> (?<!\\s):\\d+(?=\\/|$|\\s))\n" + " (?<pathquery>[A-Za-z\\d\\!\\*\\(\\)\\;\\:\\@\\&\\=\\+\\$\\,\\/\\?\\#\\[\\]\\%\\{\\}\\|\\\\\\^\\`\\~]+)\n" + " (?<url> (?&protocol) (?: (?:\\/\\/) (?: (?&domain) | (?&ip) ) (?&port)? )? (?&pathquery))\n" + ")\n" + "(?&url)"; final String string = "http://en.wikipedia.org/wiki/A#CITEREFSimpsonWeiner1989里面找 以上URL\n" + "下载地址magnet:?xt=urn:btih:65F16B126D8A656E4FC825DE204EBFAF04B070FC里面找 以上URL\n" + "magnet:\n" + "net:\n" + "以下URLhttps://en.wikipedia.org/wiki/A#CITEREFSimpsonWeiner1989里面找 以上URL\n" + "http://192.168.1.1/里面找\n" + "'https://en.wikipedia.org/wiki/A/////#CITEREFSimpsonWeiner1989'\n" + "http://192.168.1.1:80/ 里面找\n" + "以下URL\n" + "https://google.com/search?q=%E5%9F%9F%E5%90%8D#newwindow=1&q=%E5%9F%9F%E5%90%8D+%E5%AD%97%E7%AC%A6\n\n" + "http://en.wikipedia.org/wiki/A#CITEREFSimpsonWeiner1989\n" + "magnet:?xt=urn:btih:65F16B126D8A656E4FC825DE204EBFAF04B070FC\n" + "https://en.wikipedia.org/wiki/A#CITEREFSimpsonWeiner1989\n" + "http://192.168.1.1/\n" + "https://en.wikipedia.org/wiki/A/////#CITEREFSimpsonWeiner1989\n" + "http://192.168.1.1:80/\n" + "https://google.com/search?q=%E5%9F%9F%E5%90%8D#newwindow=1&q=%E5%9F%9F%E5%90%8D+%E5%AD%97%E7%AC%A6\n"; final Pattern pattern = Pattern.compile(regex, Pattern.UNICODE_CASE | Pattern.COMMENTS | 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