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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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 = "(\\w+(?=\\/NN.?|JJ))"; final String string = "(S (NP cured/VBN ham/NN))\n" + "(S (NP cured/VBN smoked/VBD beef/NN))\n" + "(S (NP curry/NN powder/NN))\n" + "(S (NP custard/NN))\n" + "(S (NP custard/NN) (NP puerto/JJ rican/JJ style/NN))\n" + "(S (NP custard-apple/NN))\n" + "(S (NP cytosport/NN muscle/NN milk/NN ready-to-drink/NN))\n" + "(S (NP daiquiri/NN))\n" + "(S (NP daiquiri/NN) (NP prepared/VBN) --/: (NP recipe/VB))\n" + "(S (NP dandelion/NN) greens/NNS)\n" + "(S (NP dandelion/NN) greens/NNS (NP cooked/VBD butter/NN))\n" + "(S (NP dandelion/NN) greens/NNS (NP cooked/VBD margarine/NN))\n" + "(S (NP dandelion/NN) greens/NNS (NP cooked/VBD oil/NN))\n" + "(S\n" + " (NP dandelion/NN)\n" + " greens/NNS\n" + " (NP cooked/VBD boiled/VBN drained/JJ salt/NN))\n" + "(S\n" + " (NP dandelion/NN)\n" + " greens/NNS\n" + " (NP cooked/VBD fat/NN)\n" + " (NP added/VBD cooking/NN ns/NN type/NN fat/NN))\n" + "(S\n" + " (NP dandelion/NN)\n" + " greens/NNS\n" + " (NP cooked/VBD fat/NN)\n" + " (NP added/VBD cooking/NN))\n" + "(S\n" + " (NP dandelion/NN)\n" + " greens/NNS\n" + " (NP cooked/VBD ns/JJ fat/NN)\n" + " (NP added/VBD cooking/NN))\n" + "(S (NP danish/JJ dessert/NN pudding/NN))\n" + "(S (NP danish/JJ pastry/NN cheese/NN))\n" + "(S (NP danish/JJ pastry/NN cinnamon/NN) (NP enriched/VBD))\n" + "(S (NP danish/JJ pastry/NN cinnamon/NN) (NP unenriched/VBD))\n" + "(S\n" + " (NP danish/JJ pastry/NN fruit/NN)\n" + " (NP\n" + " enriched/VBD\n" + " includes/VBZ\n" + " apple/NN\n" + " cinnamon/NN\n" + " raisin/NN\n" + " lemon/NN\n" + " raspberry/NN\n" + " strawberry/NN))\n" + "(S\n" + " (NP danish/JJ pastry/NN fruit/NN)\n" + " (NP\n" + " unenriched/VBD\n" + " includes/VBZ\n" + " apple/NN\n" + " cinnamon/NN\n" + " raisin/NN\n" + " strawberry/NN))\n" + "(S (NP danish/JJ pastry/NN lemon/NN) (NP unenriched/VBD))\n" + "(S (NP danish/JJ pastry/NN raspberry/NN) (NP unenriched/VBD))\n" + "(S (NP dark/JJ) (NP chocolate/VB 45-59/JJ %/NN cocoa/NN))\n" + "(S (NP dark/JJ) (NP chocolate/VB 60-69/JJ %/NN cocoa/NN))\n" + "(S (NP dark/JJ) (NP chocolate/VB 70-85/JJ %/NN cocoa/NN))\n" + "(S (NP dark/JJ chocolate/NN) (NP coated/VBD coffee/NN) beans/NNS)\n" + "(S (NP dasheen/NN) (NP boiled/VBD))\n" + "(S (NP dasheen/NN) (NP fried/VBD))\n" + "(S (NP date/NN candy/NN))\n" + "(S dates/NNS (NP deglet/VBP noor/JJ))\n" + "(S (NP decaf/NN coffee/NN))\n" + "(S (NP deer/NN chop/NN) (NP cooked/VBD))\n" + "(S (NP dehydrated/VBN milk/NN))\n" + "(S (NP dessert/NN dip/NN))\n" + "(S (NP dessert/NN pizza/NN))\n" + "(S (NP dessert/NN sauce/NN))\n" + "(S (NP dessert/NN topping/NN) (NP powdered/VBD))\n" + "(S\n" + " (NP dessert/NN topping/NN)\n" + " (NP powdered/VBD 1.5/CD)\n" + " (NP ounce/NN)\n" + " (NP prepared/VBD 1/2/CD)\n" + " cup/NNS\n" + " (NP milk/NN))"; 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