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

/
/
gms

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 = "(?:(?:(\\/)(\\*)|([\"'])).*?(?:\\2\\1|\\3))|(?:\\/\\/[^\\n]+)"; final String string = "\n" + " //get means only read, but not to mutate data\n" + " Get(BooksWithAuthors)\n" + " //default queries via mycel\n" + " .Query()\n" + " //junction table to pair books and authors\n" + " .From(\"BookAuthor\".As(BA))\n" + " //main table for books\n" + " .Join(left: Books.As(B) => B.Id == BA.BookId)\n" + " //main table for authors\n" + " .Join(left: Authors.As(A) => A.Id == BA.AuthorId)\n" + " //groups by column, body allows to restore data (restructuring)\n" + " .GroupBy(B.Id, => { B.Authors.Add(A) })\n" + " //ignore still registerd data objects for the response\n" + " .SelectIgnore(BA)\n" + " //or select only that fields or objects you want to response\n" + " .Select(B)\n" + " .Foo(\"//wrong-comment-inside-quotes\")\n" + " .Foo('//wrong-comment-inside-single-quotes')\n" + " .Foo('some /*wrong-comment*/ inside')\n" + " ;\n\n" + " //get means only read, but not to mutate data\n" + " Get(BooksWithAuthorsByMethod)\n" + " //using individual backside methods (created by own)\n" + " .GetBooksWithAuthors(id:6, filter:{key:'minAuthorAge', value:17})\n" + " ;\n\n" + " /*\n" + " comments\n" + " \"over\"\n" + "*/\n" + "/*\n" + " 'multiply\n" + " lines' //with wrong comments inside\n" + " *\\\n\n\n" + "aa\"aasdfasdasdf\n" + "asdfasdfasdf\n" + "asdfasdf\"asdfasd\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