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
Processing...

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 = "# Start defining\n" + "(?(DEFINE)\n" + " (?<XSEP>\\s*[xх\\*\\-\\s]?\\s*)\n" + " (?<MARGIN>(?:\\.\\d)?)\n" + " (?<RADIUS>r?[12]\\d(?&MARGIN))\n" + " (?<J>(?:1[01]|[4-9])(?&MARGIN)j?)\n" + " (?<DIAM>\n" + " \\b\n" + " (?:\n" + " (?&RADIUS)(?:\\s*\\/\\s*(?&J))?\n" + " |\n" + " (?&J)(?&XSEP)(?&RADIUS)\n" + " )\n" + " \\b\n" + " )\n" + " (?<PCD>\\b(?:[pb]cd\\s*)?[34568](?&XSEP)(?:98|[12]\\d{2})(?&MARGIN)\\b)\n" + " (?<ET>(?:(?:et|ет)\\s*)?\\-?\\d+(?&MARGIN)\\b)\n" + " (?<CB>\\b(?:(?:цо|cb|d(?:ia)?)\\s*)?\\d{2,3}(?&MARGIN)\\b)\n" + ")\n" + "# End defining\n" + "(?:\n" + "(?<diam>(?&DIAM))\n" + "|\n" + "(?<pcd>(?&PCD))\n" + "|\n" + "(?<et>(?&ET))\n" + "|\n" + "(?<cb>(?&CB))\n" + ")"; final String string = "r22 pcd 4x108 ET 45.5 ЦО 58.5\n" + "15 /5.0j 6*108 et45 ЦО 58.5\n" + "15/ 5.0j 4x108 -45.5 58.5\n" + "pcd 4x138 15/5.0j ET58.5 ЦО45\n" + "ЦО45.5 ET58.5 19 pcd 4x 108\n\n" + "r15/5.6j pcd 5х112 ET60 CB66\n" + "et50 r15/5 5х112 ET60 d66\n" + "r15/5 pcd 5*112 ET60 dia 66\n\n" + "5.6j x 15.5 pcd 5 х 112 ет -60 CB66\n\n" + "5x15.5 5х112.5 ET60 CB66\n\n" + "250/50 r16"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.COMMENTS | Pattern.DOTALL | Pattern.MULTILINE | Pattern.UNICODE_CASE); 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