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

r"
"
gm

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 = "^(?:\\((?P<imp>[A-Z])\\)\\ )?(?P<dued>(?:2[0-1][0-9]{2}\\-(?:0[0-9]|1[0-2])\\-(?:[0-2][0-9]|3[0-1]))|\\?)\\ (?:\\+(?P<proname>[a-zA-Z0-9]+)(?:\\#(?P<pronum>[0-9]+))?\\ )?(?:\\$(?P<startd>2[0-1][0-9]{2}\\-(?:0[0-9]|1[0-2])\\-(?:[0-2][0-9]|3[0-1]))(?:\\^(?P<repeat>\\d*(?:D|W|M|Y)(?:\\,\\d*(?:D|W|M|Y)+)*))?\\ )?(?P<todo>.+?(?=(?:\\ (?:\\@|\\&))|$))(?P<contexts>(?:\\ \\@\\S+)*)(?P<tags>(?:\\ \\&\\S+)*)"; final String string = "(A) 2016-10-23 +projectB $2016-10-03 to be completed as soon as possible @context_bar\n" + "(A) 2016-11-01 +projectA $2016-09-25 job to complete @context @context_two\n" + "(B) ? +houseworks $2016-10-04^2D,W lavoro importante &TAG_FOO &TAG_BAR\n" + "2016-12-15 +projectA#2 $2016-09-25 second job related to the same project @another_context\n" + "? +houseworks $2016-10-02^3D altro lavoro di casa @context_bar &TAG\n" + "? +projectA#3 $2016-09-25 third job of the same project @foo_context &WAIT\n" + "? +projectA#4 $2016-09-25 fourth job, needs third to be completed first\n" + "2016-11-23 $2015-06-23^4Y another job without project @context_foo @context_bar &TAG_A &TAG_B\n" + "? minimal job like email fra@me.com"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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