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

/
/
gm

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[KLRZ]|C[AOT]|D[CE]|FL|GA|HI|I[ADLN]|K[SY]|LA|M[ADEINOST]|N[CDEHJMVY]|O[HKR]|PA|RI|S[CD]|T[NX]|UT|V[AT]|W[AIVY])"; final String string = "AL Alabama\n" + "AK Alaska\n" + "AZ Arizona\n" + "AR Arkansas\n" + "CA California\n" + "CO Colorado\n" + "CT Connecticut\n" + "DE Delaware\n" + "DC District of Columbia\n" + "FL Florida\n" + "GA Georgia\n" + "HI Hawaii\n" + "ID Idaho\n" + "IL Illinois\n" + "IN Indiana\n" + "IA Iowa\n" + "KS Kansas\n" + "KY Kentucky\n" + "LA Louisiana\n" + "ME Maine\n" + "MD Maryland\n" + "MA Massachusetts\n" + "MI Michigan\n" + "MN Minnesota\n" + "MS Mississippi\n" + "MO Missouri\n" + "MT Montana\n" + "NE Nebraska\n" + "NV Nevada\n" + "NH New Hampshire\n" + "NJ New Jersey\n" + "NM New Mexico\n" + "NY New York\n" + "NC North Carolina\n" + "ND North Dakota\n" + "OH Ohio\n" + "OK Oklahoma\n" + "OR Oregon\n" + "PA Pennsylvania\n" + "RI Rhode Island\n" + "SC South Carolina\n" + "SD South Dakota\n" + "TN Tennessee\n" + "TX Texas\n" + "UT Utah\n" + "VT Vermont\n" + "VA Virginia\n" + "WA Washington\n" + "WV West Virginia\n" + "WI Wisconsin\n" + "WY Wyoming"; 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