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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

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 = "(?:<!\\[CDATA\\[(?<cdata>.*?)\\]\\]>|(?<xml><\\?.*?\\?>)|<!--(?<comment>.*?)-->|<\\s*(?<tag>[A-z][A-z0-9-_.:]*)(?:\\s+(?:[A-z][A-z0-9-_.:]*)\\s*(?:=\\s*(?<quote>[\"'])((?:\\\\\\k<quote>|(?:(?!\\k<quote>)).)*)(\\k<quote>)\\s*)?)*\\s*(?:/\\s*>|>(?<innerHTML>.*)?<\\s*/\\s*\\k<tag>\\s*>)|(?<text>[^<]*))"; final String string = "<?xml version='1.0' encoding='shift_jis'?>\n" + "<!-- foo -->\n" + "<foo>bar</foo>\n" + "Baz\n" + "<foo asdf=\"foo\" />\n" + "<CharacterInfo defaultUid=''>\n" + "<Character \n" + " name='??????'\n" + " uid='511111'\n" + " weapon='??' \n" + " HR='7' GR='0' lastLogin='1645561498'\n" + " sex='M' />\n" + "<Character name ='Potatoe/>sss' uid= '511111' weapon = '??' HR='7' GR=\"0\" lastLogin='1645561498' sex='M' />\n" + "</CharacterInfo>\n\n\n" + "Plain text\n" + "<hr/>\n" + "Multi\n" + "line\n" + "text\n" + "<br />\n" + "<!-- \n" + "This is a comment!\n" + "<foo />\n" + "-->\n" + "<foo \n" + "bar/>\n" + "<baz asdf=\"2\"></baz>\n\n" + "<asd foo=\"asd\\\"q'we\" / >\n" + "<b>Hello, <i>World</i>!</b>\n\n" + "<Character \n" + " name='??????'\n" + " uid='511111'\n" + " weapon='??' \n" + " HR='7' GR='0' lastLogin='1645561498'\n" + " sex='M' />\n" + "<Character name ='Potatoe/>sss' uid= '511111' weapon = '??' HR='7' GR=\"0\" lastLogin='1645561498' sex='M' />\n\n" + "<![CDATA[]]>\n" + "<![CDATA[Foobar<>]]>\n" + "<![CDATA[\n" + "asdasdasd\n" + "adsd\n" + "sd\n" + "sd\n" + "]]>\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL); 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