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 = "\\[\"(Total|Group1|Group2)\",(\\d+),\\d*,,,,,\\d+,\\d+\\]"; final String string = "<!DOCTYPE html>\n" + "<html class=\"main\">\n" + " <head>\n" + " <meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\" />\n" + " <title>Test_Results_20240621_0910</title>\n\n" + " <script type=\"text/javascript\" src=\"Test_Results_20240621_0910/js/jquery-1.3.2.min.js\"></script>\n" + " <script type=\"text/javascript\" src=\"Test_Results_20240621_0910/js/jquery.ui.custom-1.8.7.min.js\"></script>\n" + " <script type=\"text/javascript\" src=\"Test_Results_20240621_0910/js/jquery.dynatree-1.2.4.min.js\"></script>\n" + " <script type=\"text/javascript\" src=\"Test_Results_20240621_0910/js/jquery.cookie-1.3.1.min.js\"></script>\n" + " <script type=\"text/javascript\" src=\"Test_Results_20240621_0910/js/jquery.splitter-1.5.1.min.js\"></script>\n" + " <script type=\"text/javascript\" src=\"Test_Results_20240621_0910/js/dotcover.report.js\"></script>\n\n" + " <link rel=\"stylesheet\" type=\"text/css\" href=\"Test_Results_20240621_0910/css/dotcover.report.css\">\n" + " <link rel=\"stylesheet\" type=\"text/css\" href=\"Test_Results_20240621_0910/css/dotcover.report.gen.css\">\n" + " <link rel=\"stylesheet\" type=\"text/css\" href=\"Test_Results_20240621_0910/css/jquery.dynatree.css\">\n" + " </head>\n\n" + " <body>\n" + " <div class=\"header\"><span class=\"title\">Test_Results_20240621_0910 Coverage Report</span><span class=\"info\">Generated: Friday, June 21, 2024 09:14:13</span></div>\n" + " <div class=\"content\" id=\"content\"><div id=\"coverageTree\"></div><iframe id=\"sourceCode\"></iframe></div>\n" + " <div class=\"footer\">JetBrains dotCover 2024.1.3 Copyright &copy; 2010-2024 <a href=\"https://www.jetbrains.com/dotcover/\" target=\"_blank\">Product Homepage</a> | <a href=\"https://www.jetbrains.com/feedback/feedback.jsp?product=dotCover&build=3&timezone=Eastern Standard Time\" target=\"_blank\">Feedback</a> | <a href=\"https://www.jetbrains.com/\" target=\"_blank\">Company</a></div>\n\n" + " <script type=\"text/javascript\">\n" + " var resourceFolder = \"Test_Results_20240621_0910\";\n" + " var blockSize = 50000;\n" + " block0 = [[\"Total\",47,,,,,,1,2],[\"Group1\",29,0,,,,,3,5],[\"Group2\",52,0,,,,,8,4]];\n" + " coverageData = [block0];\n" + " </script>\n" + " </body>\n" + "</html>"; 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