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
Processing...

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 = "((anticorpi|ac|ciroza).*?)?(hepatita (cr(onica)? )?(.*?))?(vh|hv|virus )([bcd])(.*?(vh|hv|virus )([bcd]))?"; final String string = "HEPATITA CRONICA CU VHC\n" + "HEPATITA CRONICA - VHC\n" + "HEPATITA CRONICA DE ETIOLOGIE MIXTA NUTRITIONALA SI VHC\n" + "HEPATITA CRONICA CU VHC.\n" + "HEPATITA CRONICA CU VHC.\n" + "HEPATITA CRONICA CU VHC\n" + "HEPATITA CRONICA - VHB\n" + "HEPATITA CRONICA CU VIRUS C\n" + "HEPATITA CRONICA\n" + "HEPATITA CRONICA CU VHB\n" + "HEPATITA CRONICA MEDICAMENTOASA.\n" + "HEPATITA DE ETIOLOGIE POSIBIL VIRALA IN APP\n" + "HEPATITA VIRUS C\n" + "HEPATITA CRONICA CU VHB\n" + "HEPATITA CRONICA CU VHC \n" + "Hepatita cr cu virus B\n" + "HEPATITA VIRUS C\n" + "HEPATITA VIRALA (VHA-####) \n" + "HEPATITA CRONICA VHB\n" + "HEPATITA CRONICA CU VHC\n" + "HEPATITA CRONICA- VHB\n" + "HEPATITA CRONICA CU VHC \n" + "HEPATITA CRONICA CU VHC(####)\n" + "HEPATITA CRONICA DE ETIOLOGIE NEPRECIZATA \n" + "HEPATITA CRONICA CU VHB\n" + "HEPATITA CRONICA VHC\n" + "HEPATITA CRONICA VIRALA CU VHC\n" + "HEPATITA VIRALA -VHC \n" + "HEPATITA CRONICA CU VHC\n" + "Hepatita cronica cu virus B\n" + "HEPATITA CRONICA CU VHB +VHC\n" + "HEPATITA CRONICA VHB+VHC \n" + "HEPATITA VIRALA C \n" + "HEPATITA CRONICA CU VHC \n" + "HEPATITA CRONICA CU VHB\n" + "HEPATITA CRONICA VHB+VHC\n" + "HEPATITA CRONICA CU VHB \n" + "HEPATITA B\n" + "Hepatita cronica.\n" + "HEPATITA CRONICA CU VHB\n" + "CIROZA HEPATICA SECUNDARA INFECTIEI CU VHB SI VHD \n" + "CIROZA HEPATICA VHB +VHD\n" + "CIROZA HEPATICA SECUNDARA INFECTIEI CU VHB SI VHD\n" + "HVB, HVC \n" + "HVB+ HVC \n" + "HVC + HVB \n" + "HEPATITA CU HVC \n" + "HEPATITA CRONICA HVC \n" + "HEPATITA CU HVC \n" + "CIROZA HEPATICA -HVC CHILD A\n" + "Ac AntiHVC +, HEPATOSPLENOMEGALIE\n" + "HEPATITA CU HVC \n" + "HEPATITA CRONICA HVC\n" + "ANTICORPI ANTI-HVC+\n"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE); 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