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

~
~
gxsJ

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?<=^|\\v)\n" + "\\h*+\\*\\h*+\n" + "(?:\n" + " (?:\n" + " (?P<annotation>\n" + " @(?P<name>\\w++)\n" + " (?:\n" + " (?<=@param)\\h++(?P<type>\\w++(?:\\[\\])?)\\h++\\$(?P<variable>\\w++)\n" + " |(?<=@return)\\h++(?P<type>\\w++(?:\\[\\])?)\n" + " |(?<=@throws)\\h++(?P<class>\\w++)\n" + " |(?<=@cache)\\h++(?P<time>\\d++)\n" + " |(?<=@roles)\\h++(?P<roles>\\w++(?:\\h*+,\\h*+\\w++)*)\n" + " )?\n" + " )\n" + " )\n" + " (?P<comment>\\h++[^\\v]++)?\n" + " (?:(?P<comment>\\v)\\h*+\\*\\h*+(?P<comment>[^\\v@\\h\\*][^\\v]++))*+\n" + " |(?P<description>(?:[^\\v@\\h\\*][^\\v]++)\n" + " (?:\n" + " \\v\\h*+\\*\\h*+[^\\v@\\h\\*][^\\v]++\n" + " )*+\n" + " )\n" + ") "; final String string = "/**\n" + " * bla bla \n" + " *bla2 @ bla2 @\n" + " *\n" + " * bla bla 3\n" + " *\n" + " * @olivier voila\n" + " * @param string $sku1 bidule\n" + " *\n" + " * @param string[] $sku2\n" + " *\n" + " * @param string $sku3 toto bidule @\n" + " * machin truc\n" + " *\n" + " * @param string $sku4\n" + " * machin truc\n" + " *\n" + " * @deprecated\n" + " *\n" + " * @deprecated toto\n" + " *\n" + " * @throws Exception\n" + " * @throws Exception\n" + " * machin\n" + " * @return Cfe_Type_Product\n" + " * @cache 3600\n" + " * @roles toto, titi,truc , machin\n" + " */"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS | 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