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 = "<label\\b.*?(data-html=\"NewItem\").*?>.*?<\\/label>"; final String string = "<div class=\"pagination\" data-source=\"jsonfields\"><!-- Top bar content goes here --><div class=\"control\"><label class=\"btn-process jsNewItem\" data-html=\"NewItem\" data-action=\"createitem\"><span class=\"navlink-icon\"><i class=\"bx bx-list-plus\"></i></span></label><label class=\"btn-process jsPageItem active pagelink\" data-html=\"PageItem\" data-index=\"1\" data-action=\"navipage\"><span class=\"navlink-text \">1</span><!-- <span class=\"\"></span> --><!-- <input type=\"hidden\" class=\"text-input \" data-parent=\"\" name=\"\" data-suffix=\"\" value=\"\"> --></label><label class=\"btn-process jsPageItem false pagelink\" data-html=\"PageItem\" data-index=\"2\" data-action=\"navipage\"><span class=\"navlink-text \">2</span><!-- <span class=\"\"></span> --><!-- <input type=\"hidden\" class=\"text-input \" data-parent=\"\" name=\"\" data-suffix=\"\" value=\"\"> --></label></div><div class=\"parameters\"><label class=\"btn-process checkbox jsAutoItem pagelink\" data-action=\"autorefresh\"><input type=\"checkbox\" class=\"text-input jsAutoRefresh\" data-parent=\"{$CLASSPARENT_FIELDS}\" name=\"autorefresh\" {$AUTOREFRESH_FIELD}> Autorefresh</label><label class=\"btn-process jsRefreshPage pagelink\" data-action=\"refreshpage\"><span class=\"navlink-icon\"><i class=\"bx bx-refresh\"></i></span></label></div></div>\n" + "<div class=\"pagination\" data-source=\"jsonfields\"><!-- Top bar content goes here --><div class=\"control\"><label class=\"btn-process jsNewItem\" data-html=\"NewItem\" data-action=\"createitem\"><span class=\"navlink-icon\"><i class=\"bx bx-list-plus\"></i></span></label><label class=\"btn-process jsPageItem active pagelink\" data-html=\"PageItem\" data-index=\"1\" data-action=\"navipage\"><span class=\"navlink-text \">1</span><!-- <span class=\"\"></span> --><!-- <input type=\"hidden\" class=\"text-input \" data-parent=\"\" name=\"\" data-suffix=\"\" value=\"\"> --></label><label class=\"btn-process jsPageItem false pagelink\" data-html=\"PageItem\" data-index=\"2\" data-action=\"navipage\"><span class=\"navlink-text \">2</span><!-- <span class=\"\"></span> --><!-- <input type=\"hidden\" class=\"text-input \" data-parent=\"\" name=\"\" data-suffix=\"\" value=\"\"> --></label></div><div class=\"parameters\"><label class=\"btn-process checkbox jsAutoItem pagelink\" data-action=\"autorefresh\"><input type=\"checkbox\" class=\"text-input jsAutoRefresh\" data-parent=\"{$CLASSPARENT_FIELDS}\" name=\"autorefresh\" {$AUTOREFRESH_FIELD}> Autorefresh</label><label class=\"btn-process jsRefreshPage pagelink\" data-action=\"refreshpage\"><span class=\"navlink-icon\"><i class=\"bx bx-refresh\"></i></span></label></div></div>"; 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