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

~
~
mgu

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 = "^/foo/bar/+(?:(?:find|count)/*$(*SKIP)(*FAIL)|([^/\\r\\n\\t]+))/*$"; final String string = "--------------------must NOT get as id (reseved key words)\n" + "/foo/bar/count\n" + "/foo/bar/find\n" + "--------------------must NOT get as id (not present)\n" + "/foo/bar/\n" + "--------------------must NOT get as id (not present tab test)\n" + "/foo/bar/ \n" + "--------------------must NOT get as id (not present line break test)\n" + "/foo/bar/\n\n" + "--------------------must NOT get as id (not present tab, line break, multiple slashes test)\n" + "/foo/bar// /\n" + " /\n" + "//\n" + "--------------------must get as id\n" + "/foo/bar/1\n" + "/foo/bar/1c\n" + "/foo/bar/c1\n" + "/foo/bar/sku\n" + "/foo/bar/countfind\n" + "/foo/bar/findcount\n" + "/foo/bar/skucount\n" + "/foo/bar/skufind\n" + "/foo/bar/countsku\n" + "/foo/bar/findsku\n" + "/foo/bar/coun\n" + "/foo/bar/fin\n" + "/foo/bar/ount\n" + "/foo/bar/ind\n" + "/foo/bar/skucoun\n" + "/foo/bar/skufin\n" + "/foo/bar/finsku\n" + "/foo/bar/counsku\n" + "--------------------must get as id (unnecessary slash test)\n" + "/foo/bar/1/\n" + "/foo/bar/1c/\n" + "/foo/bar/c1/\n" + "/foo/bar/sku/\n" + "/foo/bar/countfind/\n" + "/foo/bar/findcount/\n" + "/foo/bar/skucount/\n" + "/foo/bar/skufind/\n" + "/foo/bar/countsku/\n" + "/foo/bar/findsku/\n" + "/foo/bar/coun/\n" + "/foo/bar/fin/\n" + "/foo/bar/ount/\n" + "/foo/bar/ind/\n" + "/foo/bar/skucoun/\n" + "/foo/bar/skufin/\n" + "/foo/bar/finsku/\n" + "/foo/bar/counsku/\n" + "--------------------must get as id (unnecessary|invalid slashed test)\n" + "/foo/bar///1///\n" + "/foo/bar///1c///\n" + "/foo/bar///c1///\n" + "/foo/bar///sku///\n" + "/foo/bar///countfind///\n" + "/foo/bar///findcount///\n" + "/foo/bar///skucount///\n" + "/foo/bar///skufind///\n" + "/foo/bar///countsku///\n" + "/foo/bar///findsku///\n" + "/foo/bar///coun///\n" + "/foo/bar///fin///\n" + "/foo/bar///ount///\n" + "/foo/bar///ind///\n" + "/foo/bar///skucoun///\n" + "/foo/bar///skufin///\n" + "/foo/bar///finsku///\n" + "/foo/bar///counsku///"; final Pattern pattern = Pattern.compile(regex, 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