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 = "((^0)\\s+|(^1)\\s+|(^2)\\s+|(^3)\\s+|(^4)\\s+|(^5)\\s+)((((.{4})(.+)))|((.{4})))"; final String string = "0 @I0066@ INDI\n" + "1 NAME Joan Adrienne /Hatch/\n" + "2 GIVN Joan Adrienne\n" + "2 SURN Hatch\n" + "2 SOUR @S0045@\n" + "3 DATA\n" + "4 TEXT Birth date: 30 May 1935 Birth place: Hennepin, Minnesota\n" + "2 SOUR @S0131@\n" + "3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A\n" + "3 DATA\n" + "4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot\n" + "5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis\n" + "5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch\n" + "3 NOTE @N0121@\n" + "2 SOUR @S0635@\n" + "3 DATA\n" + "4 TEXT Marriage date: 29 Dec 1953 Marriage place: Cook County, IL\n" + "1 SEX F\n" + "1 BIRT\n" + "2 DATE 30 MAY 1935\n" + "2 PLAC Minneapolis, Hennepin, Minnesota, USA\n" + "2 SOUR @S0045@\n" + "3 DATA\n" + "4 TEXT Birth date: 30 May 1935 Birth place: Hennepin, Minnesota\n" + "2 SOUR @S0131@\n" + "3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A\n" + "3 DATA\n" + "4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot\n" + "5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis\n" + "5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch\n" + "3 NOTE @N0125@\n" + "1 DEAT\n" + "2 DATE 14 DEC 1989\n" + "2 PLAC Nyack, Rockland, New York, USA\n" + "1 RESI\n" + "2 DATE 1 APR 1940\n" + "2 PLAC Faribault, Rice, Minnesota, USA\n" + "2 SOUR @S0131@\n" + "3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A\n" + "3 DATA\n" + "4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot\n" + "5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis\n" + "5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch\n" + "3 NOTE @N0127@\n" + "1 RESI\n" + "2 DATE 1 APR 1940\n" + "2 PLAC Faribault, Rice, Minnesota, USA\n" + "2 SOUR @S0131@\n" + "3 PAGE Source Citation: Year: 1940; Census Place: Faribault, Rice, Minnesota; Roll: T627_1953; Page: 8B; Enumeration District: 66-9A\n" + "3 DATA\n" + "4 TEXT residence date: 1 Apr 1940 residence place: Faribault, Rice, Minnesot\n" + "5 CONC a, United States birth date: May 30, 1935 birth place: Minneapolis\n" + "5 CONC , Hennepin, Minnesota, USA Name: Joan Adrienne Hatch\n" + "3 NOTE @N0129@\n" + "1 FAMC @F1196@\n" + "1 FAMS @F0129@\n" + "1 FAMS @F0260@\n" + "1 CHAN\n" + "2 DATE 31 MAR 2017\n" + "3 TIME 22:03:40"; final String subst = "\\n $1 | $2 | $3 | $4 | $5 | $6 | $7 | $8 | $9 | $10 | $11 | $12 | $13 | $14 | |"; 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