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

/
/
sU

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 = "<xf:tokeninputrow.*\\/>"; final String string = "<xf:title>{{ phrase('start_conversation') }}</xf:title>\n\n" + "<xf:breadcrumb href=\"{{ link('conversations') }}\">{{ phrase('conversations') }}</xf:breadcrumb>\n\n" + "<xf:if contentcheck=\"true\">\n" + " <div class=\"blockMessage blockMessage--error blockMessage--iconic\">\n" + " <xf:contentcheck>\n" + " <xf:if is=\"$errorUsernames is not empty\">\n" + " <div>{{ phrase('you_can_not_start_conversation_with_following_users_because_of_privacy', {'usernames': $errorUsernames|join(', ')}) }}</div>\n" + " </xf:if>\n\n" + " <xf:if is=\"$notFoundUsernames is not empty\">\n" + " <div>{{ phrase('following_users_not_found_x', {'usernames': $notFoundUsernames|join(', ')}) }}</div>\n" + " </xf:if>\n\n" + " <xf:if is=\"$recipientLimit\">\n" + " <div>{{ phrase('you_have_exceeded_allowed_number_of_recipients_x_for', {'limit': $recipientLimit}) }}</div>\n" + " </xf:if>\n" + " </xf:contentcheck>\n" + " </div>\n" + "</xf:if>\n\n" + "<xf:form action=\"{{ link('conversations/add') }}\" ajax=\"true\" draft=\"{{ link('conversations/draft') }}\" data-preview-url=\"{{ link('conversations/add-preview') }}\" class=\"block\" data-xf-init=\"attachment-manager\">\n" + " <div class=\"block-container\">\n" + " <div class=\"block-body\">\n" + " <xf:tokeninputrow name=\"recipients\" value=\"{$to}\" href=\"{{ link('members/find') }}\"\n" + " rowtype=\"fullWidth\"\n" + " label=\"{{ phrase('recipients') }}\"\n" + " explain=\"{{ phrase('separate_names_with_comma') }}\" />\n\n" + " <xf:textboxrow name=\"title\" value=\"{$title}\" rowtype=\"fullWidth noLabel\" class=\"input--title\"\n" + " maxlength=\"{{ max_length('XF:ConversationMaster', 'title') }}\"\n" + " placeholder=\"{{ phrase('title...') }}\"\n" + " label=\"{{ phrase('title') }}\" />\n\n" + " <xf:editorrow name=\"message\"\n" + " value=\"{$message}\"\n" + " attachments=\"{{ $attachmentData ? $attachmentData.attachments : [] }}\"\n" + " rowtype=\"fullWidth noLabel mergePrev\" />\n\n" + " <xf:formrow>\n" + " <xf:if is=\"$attachmentData\">\n" + " <xf:macro template=\"helper_attach_upload\" name=\"upload_block\"\n" + " arg-attachmentData=\"{$attachmentData}\"\n" + " arg-forceHash=\"{$draft.attachment_hash}\" />\n" + " </xf:if>\n\n" + " <xf:if is=\"$xf.options.multiQuote\">\n" + " <xf:macro template=\"multi_quote_macros\" name=\"button\"\n" + " arg-href=\"{{ link('conversations/multi-quote', $conversation) }}\"\n" + " arg-messageSelector=\".js-message\"\n" + " arg-storageKey=\"multiQuoteConversation\" />\n" + " </xf:if>\n\n" + " <xf:button class=\"button--link u-jsOnly\" data-xf-click=\"preview-click\" icon=\"preview\" />\n" + " </xf:formrow>\n\n" + " <xf:checkboxrow>\n" + " <xf:option name=\"open_invite\" checked=\"{{ ($draft.open_invite OR $conversation.open_invite) ? 'checked' : '' }}\">\n" + " {{ phrase('allow_anyone_in_conversation_to_invite_others') }}\n" + " </xf:option>\n\n" + " <xf:option name=\"conversation_locked\" checked=\"{{ ($draft.conversation_open OR $conversation.conversation_open) ? '' : 'checked' }}\">\n" + " {{ phrase('lock_conversation_no_responses_will_be_allowed') }}\n" + " </xf:option>\n" + " </xf:checkboxrow>\n" + " </div>\n" + " <xf:submitrow submit=\"{{ phrase('start_conversation') }}\" sticky=\"true\" icon=\"conversation\">\n" + " <xf:html>\n" + " <xf:button class=\"u-jsOnly\" data-xf-click=\"preview-click\" icon=\"preview\" />\n" + " </xf:html>\n" + " </xf:submitrow>\n" + " </div>\n" + "</xf:form>"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL | Pattern.UNICODE_CHARACTER_CLASS); final Matcher matcher = pattern.matcher(string); if (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