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"
"
gs

Test String

Code Generator

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|\\n{2})(?:(?!\\n{2}).)+\\.(?=\\n{2}|\\Z)"; final String string = "Diagnosis of one of the following: A) Neovascular (wet) age-related\n" + "macular degeneration OR B) Macular edema following retinal vein\n" + "occlusion, OR C) Diabetic macular edema OR D) Diabetic retinopathy in\n" + "patients with diabetic macular edema. More text here.\n\n" + "PA Criteria\n\n" + "Criteria Details\n\n\n" + "Eylea (s)\n\n" + "Products Affected\n" + " EYLEA\n\n" + "Exclusion\n" + "Criteria\n\n" + "Required\n" + "Medical\n" + "Information\n\n" + "Age Restrictions\n\n" + "Prescriber\n" + "Restrictions\n\n" + "Coverage\n" + "Duration\n\n" + "Other Criteria\n\n" + "Off Label Uses\n\n\n\n\n\n\n\n\n\n\n\n" + "12 months\n\n" + "Indications\n\n" + "All Medically-accepted Indications.\n\n" + "Formulary ID 20276, Version 12\n\n" + "101"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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