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

/
/
g

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 = "<([^> ]+)[^>]*>[^<]*<([^> ]+)[^>]*>(\\{\\{.*\\}\\})<\\/\\2>[^<]*<\\/\\1>"; final String string = "# <td><p>{{README.README}}</p></td>\n" + "# My soluction is independent of the HTML tags which make it very flexible.\n" + "# Work with javascript, python and php(probably you are using javascript).\n" + "#\n" + "# Alternative soluctions... copy and try!\n" + "# More expecific:\n" + " <([^> ]+)[^>]*>[^<]*<([^> ]+)[^>]*>({{custom.amountTable}})<\\/\\2>[^<]*<\\/\\1>\n" + "# More expecific and faster:\n" + " <(tr)[^>]*>[^<]*<(td)[^>]*>({{custom.amountTable}})<\\/\\2>[^<]*<\\/\\1>\n" + "<thead>\n" + "<tr style=\"background-color: #487cdb; text-align: center;\">\n" + "<td style=\"width: 224px;\">qwerqwerqwer</td>\n" + "<td style=\"width: 224px;\">qwerqwerqwer</td>\n" + "<td style=\"width: 225px;\">qwerqwerqwer</td>\n" + "</tr>\n" + "</thead>\n" + "<tbody>\n" + "<tr>\n" + "<td style=\"width: 224px;\">&nbsp;</td>\n" + "<td style=\"width: 224px;\">&nbsp;</td>\n" + "<td style=\"width: 225px;\">&nbsp;</td>\n" + "</tr>\n" + "<tr style=\"text-align: center;\">\n" + "<td style=\"width: 224px;\" colspan=\"3\">{{custom.amountTable}}</td>\n" + "</tr>\n" + "<tr>\n" + "<td style=\"width: 224px;\">&nbsp;</td>\n" + "<td style=\"width: 224px;\">&nbsp;</td>\n" + "<td style=\"width: 225px;\">&nbsp;</td>\n" + "</tr>\n" + "</tbody>\n" + "</table>\n\n" + "# <td><p>{{HEY.FYI}}</p></td>\n" + "# I could make a function that generate the regex dinamicly, for example you \n" + "# could pass the expecific {{custom.property}} part \n" + "# and the level of HTML tags to match\n" + "# matchFunction('custom.amountTable', 2))\n\n" + "<tag whatever=\"property\">\n" + "<anothertag>{{custom.whatever}}</anothertag>\n" + "</tag>\n\n" + "<td><p>{{custom.whatever}}</p></td>\n\n\n" + "#Junior Báez: https://www.linkedin.com/in/jrbaez01/"; final Pattern pattern = Pattern.compile(regex); 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