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 = "\\b[A-Z][a-z]+\\b\\s+\\b[A-Z][a-z]+\\b"; final String string = "54. Mikhail Stepanovich ZUSKO\n" + "(Михаил Степанович ЗУСЬКО)\n" + "Function: Russian military leader – Lieutenant- General\n" + "Chief of staff of the “West” grouping\n" + "Former Commander of the 58th Combined Arms Army of the Southern Military District\n" + "DOB: 24.5.1972\n" + "POB: Vetly, Volyn region, former Ukrainian SSR (now Ukraine)\n" + "Nationality: Russian\n" + "Gender: male\n" + "Associated entities: Ministry of Defence of the Russian Federation\n\n" + "55. Mikhail Yuryevich TEPLINSKIY\n" + "(Михаил Юрьевич ТЕПЛИНСКИЙ) \n" + "Function: Russian military leader – Colonel-General\n" + "Commander of Airborne Forces of the Armed Forces of the Russian Federation\n" + "DOB: 9.1.1969\n" + "POB: Mospino, Donetsk oblast, former Ukrainian SSR (now Ukraine)\n" + "Nationality: Russian\n" + "Gender: male\n" + "Associated entities: Ministry of Defence of the Russian Federation\n\n" + "56. Nikolay Mikhailovich PARSHIN\n" + "(Николай Михайлович ПАРШИН) \n" + "Function: Russian military leader – Lieutenant- General\n" + "Head of the Main Rocket and Artillery Directorate of the Ministry of Defense of the Russian Federation\n" + "DOB: 20.12.1962\n" + "POB: The village of Mordovskoye- Kolomasovo, former Mordovian ASSR (now Russian Federation)\n" + "Nationality: Russian\n" + "Gender: male\n" + "Associated entities: Ministry of Defence of the Russian Federation\n\n" + "57. Oleg Yurievich TSOKOV\n" + "(Олег Юрьевич ЦОКОВ) \n" + "Function: Russian military leader – Major-General\n" + "Commander of the 144th Motor Rifle Division of the 20th Combined Arms Army of the Armed Forces of the Russian Federation\n" + "DOB: 23.9.1971\n" + "POB: former USSR (now Russian Federation)\n" + "Nationality: Russian\n" + "Gender: male\n" + "Associated entities: Ministry of Defence of the Russian Federation\n\n" + "58. Ramil Rakhmatulovich IBATULLIN\n" + "(Рамиль Рахматуллович ИБАТУЛЛИН)\n" + "Function: Russian military leader – Major-General\n" + "Commander of the 90th Guards Tank Division\n" + "DOB: 22.10.1976\n" + "POB: Bagishevo, Apastovsky District, Tatarstan, former USSR (now Russian Federation)\n" + "Nationality: Russian\n" + "Gender: male\n" + "Associated entities: Ministry of Defence of the Russian Federation\n\n" + "59. Sergey Viktorovich KARAKAEV\n" + "(Сергей Викторович КАРАКАЕВ) \n" + "Function: Russian military leader – Colonel-General\n" + "Commander of the Strategic Missile Forces\n" + "DOB: 4.6.1961\n" + "POB: The village of Ivano-Slyusarevka, Krasnodar Territory, former USSR (now Russian Federation)\n" + "Nationality: Russian\n" + "Gender: male\n" + "Associated entities: Ministry of Defence of the Russian Federation\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