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 = "https:\\/\\/\\S+\\/[a-z-0-9\\?=]+-+\\d+-+"; final String string = "nav=\"true\">Upgrade</a></div></div></header><div class=\"js-streamItemList\"><div class=\"streamItem streamItem--readingListPostItem js-streamItem\"><section class=\"u-paddingTop20 u-paddingBottom20 u-borderBottomLightest u-maxWidth740\"><div class=\"u-flexTop\"><div class=\"u-flex1 u-width560\"><a class=\"link link--noUnderline u-baseColor--link\" href=\"https://becominghuman.ai/exporting-cassandra-time-series-data-to-s3-for-data-analysis-using-spark-ca9337990a21?source=bookmarks---------0---------------------\"><h3 class=\"u-paddingTop4 u-contentSansBold u-fontSize22 u-textColorDarkest u-maxHeight2LineHeightTighter u-lineClamp2 u-textOverflowEllipsiadingTime\" title=\"6 min read\"></span></div></div><a class=\"link link--noUnderline u-baseColor--link\" href=\"https://becominghuman.ai/exporting-cassandra-time-series-data-to-s3-for-data-analysis-using-spark-ca9337990a21?source=bookmarks---------0---------------------\"><div class=\"u-flex0 u-width80 u-marginLeft40\" style=\"height: 80px; background-image: url(&quot;https://cdn-images-1.medium.com/fit/c/72/72/1*s-_xasoH65yaxSWqmezjTA.png&quot;); background-position: 50% 50% !import1 u-width560\"><a class=\"link link--noUnderline u-baseColor--link\" href=\"https://hackernoon.com/how-to-create-simple-rest-apis-with-springboot-79148ac90efd?source=bookmarks---------1---------------------\"><h3 class=\"u-paddingTop4 u-contentSansBold u-fontSize22 u-textColorDarkest u-maxHeight2LineHeightTighter u-lineClamp2 u-textOverflowEllipsis u-patime datetime=\"2019-01-25T23:07:22.508Z\">Jan 26</time><span class=\"middotDivider u-marginLeft3 u-marginRight3\"></span><span class=\"readingTime\" title=\"7 min read\"></span></div></div><a class=\"link link--noUnderline u-baseColor--link\" href=\"https://hackernoon.com/how-to-create-simple-rest-apis-with-springboot-79148ac90efd?source=bookmarks---------1---------------------\"><div class=\"u-flex0 u-width80 u-marginLeft40\" style=\"height: 80px; background-image: url(&quot;https://cdn-images-1.medium.com/fit/c/72/72/0*3WmoDj3kwKL3koI6&quot;); background-position: 50% 50% !important;\"><span class=\"u-textScreenReader\">How to create simple rest apis with springboot</span></div></a></div><ul class=\"u-flexCenter u-fontSize14 u-textColorNormal\"><li><button class=\"button button--chromeless u-baseColor--buttonNormal\" data-action=\"remove-from-queue\">Remove</button></li></ul></section></div></div></div></div></div></div>"; 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