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

Substitution

Processing...

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 = "^(?=\\S.+\\nCoverage\\sLevel)|^(?=\\S.+\\nNon-Covered\\s)"; final String string = "Out of Pocket (Stop Loss)\n" + "Coverage Level: Individual\n" + "Service Type: Health Benefit Plan Coverage\n" + "Insurance Type Code: HM Health Maintenance Organization (HMO)\n" + "Time Period Qualifier: Calendar Year\n" + "Amount: $8,500.00\n" + "In Plan Network Indicator: Unknown\n" + "Deductible\n" + "Coverage Level: Individual\n" + "Service Type: Vision (Optometry)\n" + "https://luna.ema.md/ema/patient/InsuranceOverviewForm.action?pic1.0u85-w2bBh0R86_K9v71KolpMN1sZmZ0Lxolu1TW4qD3al-JJFDVNX81... 13/172/21/22, 10:26 AM Luna Dermatology: Patient Insurance\n" + "Insurance Type Code: HM Health Maintenance Organization (HMO)\n" + "Plan Coverage Description: Fidelis Care Silver\n" + "Amount: $0.00\n" + "Authorization/Certification Req'd: No\n" + "In Plan Network Indicator: no\n" + "Co-Payment\n" + "Coverage Level: Individual\n" + "Service Type: Vision (Optometry)\n" + "Insurance Type Code: HM Health Maintenance Organization (HMO)\n" + "Plan Coverage Description: Fidelis Care Silver\n" + "Amount: $0.00\n" + "Authorization/Certification Req'd: No\n" + "In Plan Network Indicator: Yes\n" + "Co-Insurance\n" + "Coverage Level: Individual\n" + "Service Type: Vision (Optometry)\n" + "Insurance Type Code: HM Health Maintenance Organization (HMO)\n" + "Plan Coverage Description: Fidelis Care Silver\n" + "Authorization/Certification Req'd: No\n" + "In Plan Network Indicator: Unknown\n\n" + "Out of Pocket (Stop Loss)\n" + "Coverage Level: Family\n" + "Service Type: Health Benefit Plan Coverage\n" + "Insurance Type Code: HM Health Maintenance Organization (HMO)\n" + "Time Period Qualifier: Remaining\n" + "Amount: $16,190.82\n" + "In Plan Network Indicator: Unknown\n" + "Non-Covered\n" + "Coverage Level: Individual\n" + "Service Type: Medical Care\n" + "Insurance Type Code: HM Health Maintenance Organization (HMO)\n" + "Plan Coverage Description: Fidelis Care Silver\n" + "In Plan Network Indicator: No\n" + "Message: Medical Care\n" + "Non-Covered\n" + "Coverage Level: Individual\n" + "Service Type: Durable Medical Equipment Purchase\n" + "Insurance Type Code: HM Health Maintenance Organization (HMO)\n" + "Plan Coverage Description: Fidelis Care Silver\n" + "In Plan Network Indicator: No\n" + "Message: DME Purchase"; final String subst = "\\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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