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

/
/
g

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 = "<userConfiguration\\s*id=(?<Id>[.]|[^<]*)>\\s*<user\\s*FullName=\\\"(?<FullName>[.]|[^\\\"]*)\\\"\\s*LoginName=\\\"(?<LoginName>[.]|[^\\\"]*)\\\"\\s*Group=\\\"(?<Group>\\d{1,3})"; final String string = "<userConfiguration id=\"myId\">\n" + " <user FullName=\"\" LoginName=\"User-1-LoginName\" Group=\"0\" Level=\"0\" StartingDate=\"2020-08-04\" ExpiredDate=\"2021-02-05\" salt=\"4Bn0RL/qMZeBFIck+o+oHCVLtRwJzgxN4tAUV4zhCUMZSVNpdhkgguPuLCt4/k4L\" data=\"dXBIUUqmYsJ5llcDKHGbYahM8YETEpkx31n+ridQKZD6QtxtuBtgsD6+kkI0YGRleV17O3aN4ieCCjJ3l1IdEOvD4jjb8NTFCr4vXZHh2K+hhl9LyisKopbkNbo6ExHC4f1RC4RNJDTcHrTp7SqetpSYzvQ/Tn8/0r/PLGlbOn2ihbTtZkC+r4QSKjAtE21sB0bvBrCd8yyI37vbLqfJrXs0mVyll63AdNcfzNWoMETNEIZWGiWyRw+nOlC8gA3ag4909dR6rk7vX3lBSNgUBwegcTeJyznpZLq5yppj5vTQe0kZZbbfxuFcDEktyH4O\"/>\n" + " <encodedData><![CDATA[[header]\n" + "Description=User Configuration file for WTT_ENC\n" + "Version=4\n" + "User=eckrodt\n" + "Timestamp=05.08.2020 13:42:48\n" + "Tool=M1ServiceCenter\n" + "LicenseOption=1\n" + "[body]\n" + "IZ4J7wFwyNRZn9syvJSQhJFo8Oipq15O4Ybe5a/sv65uqXI3d6lDY1rb5IrtF/r95PegytemC+6lxuQxwptSjKF2gRUZB3vN\n" + "Q8HXbP3OWh2gImJHjc6Yz+Tw6f+D+Herq/Plr6LMh2in1mKfiuof]]></encodedData>\n" + "</userConfiguration>\n\n" + "<userConfiguration\\s*id=(?<Id>[.]|[^<]*)>\\s*<user\\s*FullName=\\\"(?<FullName>[.]|[^\\\"]*)\\\"\\s*LoginName=\\\"(?<LoginName>[.]|[^\\\"]*)\\\"\\s*Group=\\\"(?<Group>\\d{1,3})"; final Pattern pattern = Pattern.compile(regex); 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