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 = "(PI~)([0-9]*)"; final String string = " MSH|^~\\&|EPIC|UMCG|||20180927143440||ADR^A19|18093|P|2.4|||||||||||\n" + "MSA|CA|20180927023440||\n" + "QRD|20180927|R|I|20180927|||1^RD|1414141|DEM\n" + "EVN|A19|20180927143440|||^^^^^^^^^^^^^||\n" + "PID|1||1414141^^^UMCG^PI~109819226||PROEFPERSOON&&PROEFPERSOON^J^X Y Z^^^^L^^^^NL1~PROEFPERSOON&&PROEFPERSOON^PIET^^^^^N^^^^NL1||19700101|M|PROEFPERSOON^PIET^^||PROEFLAAN 1C&PROEFLAAN&1C^^GRONINGEN^^9713GZ^NLD^L||050-1234567^P^PH^^^050^1234567~^NET^Internet^PIET@PROEFPERSOON.com~06-12345678^P^CP^^^06^12345678|06-87654321^P^PH^^^06^87654321|NEDERLANDS|||19764||||||Y||||||N||\n" + "ROL|1|UP|PP^Primary Care Provider|01001234^Huisarts^H^^^^^^Vektis^L|||||01^Huisartsen^Vektis||Straatweg 2&Straatweg&2^^Groningen^^9723AA^^O|050-3134102^WPN^PH~^NET^X.400^800013630\n" + "PV1|1|I|UG_V_A1VA^4^4-1^10^^^^^UMCG A1VA^^DEPID|NB||||||||||WOON|||||19764|CZ||||||||||||||||||||||||20180926143019||||||99996||||\n" + "AL1|1|SYSTEMISCH|^GEEN BEKENDE ALLERGIEEN^||||||\n" + "IN1|1||7119^^^UZOVI^PAYORID|CZ GROEP ZORGVERZEKERAAR UA (7119)|POSTBUS 4400&POSTBUS 4400&^^GOES^^4460CZ^||0113-274727^^^^^0113^274727|||||||||PROEFPERSOON^J^X Y Z.^^|Zelf|||Accepteren||1|||Ja||||||||||2552|ABC0123|||||||||||BEIDE||\n" + "IN2|||||Verzekeraar||||||||||||||||||||||||||||||||||||||||||||||||||||||||ABC0123|||||||||\n" + "L|1|UP|PP^Primary Care Provider|01001234^Huisarts^H^^^^^^Vektis^L|||||01^Huisartsen^Vektis||Straatweg 2&Straatweg&2^^Groningen^^9723AA^^O|050-3134102^WPN^PH~^NET^X.400^800013630\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