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

r"
"
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 = "^([A-Za-z./\\-\\(\\=><) ]+:?\\*?|^[A-Za-z./\\-\\(\\=><)0-9 ]+:+?|^[A-Za-z0-9/\\-\\(]+)? *?(([0-9\\*]+)(\\.|\\-)*([0-9\\*]+)*)([a-zA-Z./% ]*) ?([0-9.\\-= ]+)? ?(?![0-9]+)([a-zA-Z./% ]+)?$"; final String string = "Platelet Count : 297 10 ^ 3/c.mm150 - 450\n" + "Total T3 (Tri-iodothyronine) : 86.99 ng/dl 58 - 159\n" + "Bilirubin (Direct) SERUM 0.32 0 - 0.50 mg/dl\n" + "Total Cholesterol SERUM 180.00 0 - 200 mg/dl\n" + "Packed Cell Volume : 39.7 % 36.0 - 46.0\n" + "asd123\n" + "y Q P Age /Sex * 45Years / Female123asd\n" + "Blood Sugar Fasting PLASMA 92 70 - 105 mg/dl\n" + "Referred By : QUANTUM CORPORTAE HEALTH Age /Sex : 32 Years Male\n" + "Packed Cell Volume : 39.7 % 36.0 - 46.0\n" + "Platelet Count : 341 10 * 3/c.mm150 - 400\n" + "Uric Acid SERUM 8.42* 3.50-7.20 mg/dl\n" + "SERUM TOTAL CHOLESTEROL 180 mg/dl 123Desirable\n" + "ESR :* 22 mm / thr. 0-12\n" + "Haemoglobin - 12.4 gm % 12.0 - 15.0\n" + "Erythrocytes : 4.30 mill/c.mm 3.8 - 4.8\n" + "MCHC :* 31.4 g/dl 31.5 - 34.5\n" + "MPV :* 8.7 fl 9.0 - 13.0\n" + "Neutrophils - 62 % 40 - 80\n" + "Eosinophils 4-3 % 1-6\n" + "ABO And RhD Typing : A - positive\n" + "Poikilocytosis 5 *\n" + "Referred By : Quantum Corportae Health Pvt Ltd Ace Sen seme . Yeas. / Female\n\n" + "^([A-Za-z./\\-\\(\\) ]+|^[A-Za-z0-9/\\-\\(]+) +([0-9.\\-]+) *([a-zA-Z/%1 ]*) +([0-9./\\-= ]+)* *([A-Za-z/]*)\n\n\n" + "^([A-Za-z./\\-\\(\\=><) ]+|^[A-Za-z0-9/\\-\\(]+) *([0-9.\\*-]+)([a-zA-Z./% ]*) +([0-9.\\-= ]+)* *([A-Za-z/]*)"; 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