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 = "^(?:#JSGF) (?<version>V1.0) (?<encoding>[A-Z-0-9]+) (?<locale>[a-z]{2}-[A-Z]{2});$"; final String string = "#JSGF V1.0 UTF-8 hu-HU;\n" + "grammar planmaster.hu;\n" + "<command_change_odontogram> = ( <change_to> [ a ] <odontogram_mode> [ felvételére | felvételre ] ) | ( <odontogram_mode> felvétele ) ;\n" + "<change_to> = ( váltás | válts | menj | ugrás | ugorj ) ;\n" + "<odontogram_mode> = ( státuszra | státuszhoz | státusz ) {state} | ( kezelés | kezelésre | kezeléshez | lépésekre | lépésekhez ) {treatment} ;\n" + "<command_full_jaw> = <all> * ( alsó {lower} | felső {upper} ) [ fogsor | állkapocs | fogak | fog ] <all> * <status> ;\n" + "<all> = mind | összes | teljes ;\n" + "<status> = ( <status1> | <status2> | <status3> ) {status} ;\n" + "<status1> = ( ép | alaphelyzet | alaphelyzetbe ) {1} ;\n" + "<status2> = ( hiány | hiányzik ) {2} ;\n" + "<status3> = [ szekunder ] ( szuvas | szuvasodott | szuvasodás ) {3} ;\n" + "<tooth18> = ( 18as | 18-as | tizennyolcas | nyolcas | ( 18 as ) ) {18} ;\n" + "<tooth17> = ( 17es | 17-es | tizenhetes | hetes | ( 17 es ) ) {17} ;\n" + "<tooth16> = ( 16os | 16-os | tizenhatos | hatos ) {16} ;\n" + "<tooth_region> = ( bal {left} | jobb {right} ) ( felső {upper} | alsó {lower} ) ;\n" + "<tooth_number> = ( <tooth18> | <tooth17> | <tooth16> | és ) ;\n" + "<command_select> = ( ( <tooth_number> + ) | <tooth_region> <tooth_number> + ) [ fog | fogak ] ;\n"; 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