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

/
/
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 = "^_.*(*SKIP)(*F)|\\[\\[|]]"; final String string = "## [[zoom]] _[v]_\n\n" + ">[[move]] | [[very]] | [[quickly]]\n\n" + "__Synonyms__: [[buzz]] | [[dart]] | [[dash]] | [[dive]] | [[flash]] | [[fly]] | [[hum]] | [[hurtle]] | outstrip | [[rip]] | [[rocket]] | [[rush]] | [[shoot]] | [[shoot]] up | [[skyrocket]] | [[speed]] | [[streak]] | [[surge]] | [[tear]] | [[whirl]] | [[whiz]] | [[zip]]\n\n" + "__Concepts__: [[ACTIONS - MOTION#move oneself quickly (150)\\|move oneself quickly]] \n\n" + "__Antonyms__: decelerate, [[slow]]\n\n" + "## [[zip]] _[n]_\n\n" + ">[[enthusiasm]], [[energy]]\n\n" + "__Synonyms__: brio | [[drive]] | [[get]]-upand-[[go]] | [[go]] | [[gusto]] | [[life]] | liveliness | [[oomph]] | [[pep]] | [[pizzazz]] | [[punch]] | [[sparkle]] | [[spirit]] | [[verve]] | [[vigor]] | vim | [[vitality]] | [[zest]] | [[zing]]\n\n" + "__Concepts__: [[LIFE FORMS - GENERAL CHARACTERISTICS#personality (411)\\|personality]], [[STATES - ABSTRACT#behavior (633)\\|behavior]] \n\n" + "__Antonyms__: [[apathy]], enervation, [[idleness]], [[laziness]], [[lethargy]]\n" + " \n" + "## [[zip]] _[v]_\n\n" + ">[[move]] | [[about]] | [[quickly]]\n\n" + "__Synonyms__: [[bustle]] | [[dash]] | [[flash]] | [[fly]] | [[hasten]] | [[hurry]] | [[run]] | [[rush]] | [[shoot]] | [[speed]] | [[tear]] | waltz | [[whisk]] | [[whiz]] | [[zoom]]\n\n" + "__Concepts__: [[ACTIONS - MOTION#move oneself quickly (150)\\|move oneself quickly]] \n\n" + "__Antonyms__: decelerate, [[slow]]"; 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