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

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*<dd3:[^>]*>).*?>([^< ]+)<"; final String string = "PUT /mg/co.xml HTTP/1.1\n" + "Host: 19.16.7.59\n" + "User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:31.0) Gehko/20100101 Firefox/31.0\n\n" + "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" + "<!-- THIS DATA SUBJECT TO DISCLAIMER(S) INCLUDED WITH THE PRODUCT OF ORIGIN. -->\n" + "<io:zzzz xmlns:io=\"http://kfj/ledm/iomgmt/2008/11/30\" xmlns:dd=\"http://jkfhkj/dictionaries/1.0/\" xmlns:dd3=\"http://jfja/dictionaries/2009/04/06\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:schemaLocation=\"http://jcjhjk/ledm/iomgmt/2008/11/30 ../../schemas/gfjbj.xsd\">\n" + " <io:aaaa>\n" + " <dd3:bbbb>hjgjg</dd3:bbbb>\n" + " </io:aaaa>\n" + " <io:ccccc>\n" + " <io:dddd>\n" + " <dd3:ffff>15.34.2.5</dd3:ffff>\n" + " </io:dddd>\n" + " <io:eeee>\n" + " <dd3:gggg>67</dd3:gggg>\n" + " </io:eeee>\n" + " <io:iiii>\n" + " <dd3:jjjj><script>jgfjkgkj</script></dd3:jjjj>\n" + " </io:iiii>\n" + " </io:cccc>\n" + "</io:zzzz>"; 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