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

/
/

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 = "(?:\\bSECOND\\sLEVEL(\\n\\s+.*)*Dining:)(.*\\b)"; final String string = " MAIN LEVEL\n" + " Entrance: 11\n" + " Living: 22\n" + " Dining: 333\n" + " Kitchen: 444\n" + " Family: 555\n" + " Bedrooms: 666\n" + " Den: 777\n" + " Full Bath: 888\n" + " Part Bath: 999\n" + " Laundry: 000\n" + " Other 1 Name: FuckMe\n" + " Other 1 Count: 6969\n" + " Other 2 Name: Bsother2\n" + " Other 2 Count: 9696\n" + " Other 3 Name: 3\n" + " Other 3 Count: 2\n\n" + " SECOND LEVEL\n" + " Entrance: 1111\n" + " Living: 2222\n" + " Dining: 3333\n" + " Kitchen: 4444\n" + " Family: 5555\n" + " Bedrooms: 6666\n" + " Den: 7777\n" + " Full Bath: 8888\n" + " Part Bath: 9999\n" + " Laundry: 0000\n" + " Other 1 Name: Bsother\n" + " Other 1 Count: 4\n" + " Other 2 Name: Bsother2\n" + " Other 2 Count: 5\n" + " Other 3 Name: 3\n" + " Other 3 Count: 9\n\n" + " THIRD LEVEL\n" + " Entrance: 3333\n" + " Living: 334\n" + " Dining: 3332\n" + " Kitchen: 33336\n" + " Family: 33332\n" + " Bedrooms: 33338\n" + " Den: 3331336\n" + " Full Bath: 363933\n" + " Part Bath: 3655733\n" + " Laundry: 335525\n" + " Other 1 Name: Bsother\n" + " Other 1 Count: 2\n" + " Other 2 Name: Bsother2\n" + " Other 2 Count: 2\n" + " Other 3 Name: 3\n" + " Other 3 Count: 2\n\n" + " OTHER LEVEL\n" + " Level Name: Basement\n" + " Entrance: 1\n" + " Living: 1\n" + " Dining: 2\n" + " Kitchen: 1\n" + " Family: 1\n" + " Bedrooms: 1\n" + " Den: 1\n" + " Full Bath: 1\n" + " Part Bath: 1\n" + " Laundry: 1 "; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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