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

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 = "^((NA?TU?RE?S?\\s?OWN\\b)|(NAT\\s?\\.?OWN\\b)|(N\\s?\\W?\\.?O\\.?\\b)|(N\\.\\sOWN\\b)|(NATURE\\W?S\\b)|(NATURE\\sO\\b))"; final String string = "N O 100% WHOLE WHEAT\n" + "N O BUTTER BREAD\n" + "N O HONEY WHT\n" + "N O LIGHT HONEY\n" + "N O LIGHT WHEAT\n" + "N O WHITE WHEAT HAMS\n" + "N O WHITE WHEAT HOTDOGS\n" + "N. OWN HONEY WHEAT BUN\n" + "N.O 6CT 100% WHOLE\n" + "N.O 6CT MULTI GRAIN\n" + "N.O. 100% W WHEAT\n" + "N.O. 100% W WHEAT\n" + "N.O. HEALTHY\n" + "N.O. Original Bagel 20 OZ\n" + "N.O. WHITE WHEAT\n" + "N.O.ALL NATURAL 12 GRAIN\n" + "N.O.ALL NATURAL WH WHT\n" + "N/O BUTTER HAMBURGER BUN\n" + "N/O DOUBLE FIBER WHEAT\n" + "NAT OWN BTR HOT DOG BUNS\n" + "NAT OWN CIN RAISIN\n" + "NAT OWN ENG MUF\n" + "NAT OWN HNY WHT HD BUNS\n" + "NAT.OWN ORG HONEY WHEAT\n" + "NATURE O BREAD 100% WHL WHEAT W/ HONEY 16 OZ\n" + "NATURES 16 OZ SGRFR WHOL GRN\n" + "NATURE'S 2/20Z 100% WHEAT BRD\n" + "NATURE'S 2/20Z 100% WHEAT BRD\n" + "NATURE'S 2/20Z BUTTER BREAD\n" + "NATURE'S 2/20Z BUTTER BREAD\n" + "NATURE'S 2/20Z HONEY WHEAT\n" + "NATURE'S 2/20Z HONEY WHEAT\n" + "NATURE'S 24 OZ DOUBLE FIBER\n" + "NATURES OWN BUTTER ROLLS\n" + "NATURES OWN CINNAMON RAIS\n" + "NATURES OWN HONEY WHEAT THIN 20 OZ \n" + "NATURES OWN HONY 7 GRAIN\n" + "NATURES OWN LIFE 7 GRAINS\n" + "NATURES OWN LIFE WHEAT & PROTEIN BREAD\n" + "NO 100% W G WHEAT BREAD\n" + "NO 100% WHL GRN OVAL\n" + "NO ALL NAT HNY WHT BRY\n" + "NO SGR FRE WHOLE GRAIN\n" + "NO WHITE/WHEAT ROUND TOP\n" + "NTRS OWN HNY OAT SOFT\n" + "NTRS OWN HOTS NTRS OWN HOTS"; 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