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 = "translate\\(\\'([^)]*)\\',"; final String string = "<div class=\"row\">\n" + " <div class=\"col-md-12\">\n" + " <div class=\"content-title\"><?php echo $this->translate('Contattaci'); ?></div>\n\n" + " <?php if ( $this->messageProcessed && $this->sendError ): ?>\n" + " <div class=\"alert alert-danger\">\n" + " <h4><span class=\"glyphicon glyphicon-exclamation-sign\"></span> <?php echo $this->translate('Errore Invio Messaggio'); ?></h4>\n" + " <?php echo $this->translate('Spiacenti, si &eacute; verificato un errore durante l&rsquo;invio del messaggio'); ?>.\n" + " <p class=\"error\"><?php echo $this->sendError; ?></p>\n" + " </div>\n" + " <?php elseif ( $this->messageProcessed & !$this->sendError ): ?>\n" + " <div class=\"alert alert-success\">\n" + " <h4><span class=\"glyphicon glyphicon-ok-circle\"></span> <?php echo $this->translate('Messaggio Inviato'); ?></h4>\n" + " <?php echo $this->translate('Grazie per il tuo messaggio. Risponderemo nel pi&uacute; breve tempo possibile'); ?>.\n" + " </div>\n" + " <?php else: ?>\n" + " <div class=\"well well-sm\">\n" + " <?php echo $this->translate('Compila il modulo seguente per inviarci un tuo messaggio.'); ?><br />\n" + " <?php echo $this->translate('Sarà nostra premura rispondere nel minor tempo possibile per fornirti tutte le informazioni di cui puoi necessitare.'); ?>\n" + " </div>\n" + " <?php if ( $this->getSetting('site_phone') ): ?>\n" + " <div class=\"alert alert-info alert-dismissable\">\n" + " <button aria-hidden=\"true\" data-dismiss=\"alert\" class=\"close\" type=\"button\">×</button>\n" + " <span class=\"glyphicon glyphicon-info-sign\"></span> <?php echo $this->translate('Se preferisci, puoi contattarci telefonicamente al numero <b>%s</b>', $this->getSetting('site_phone')); ?>\n" + " </div>\n" + " <?php endif; ?>\n" + " <div class=\"contact-form\">\n" + " <?php echo $this->form; ?>\n" + " <div class=\"clearfix\"></div>\n" + " <p>&nbsp;</p>\n" + " <div class=\"small text-justify well well-sm\">\n" + " <?php echo $this->translate('I dati personali saranno trattati ai sensi del D.Lgs. 196/2003, sulla tutela delle persone e di altri soggetti rispetto al trattamento dei dati personali, il trattamento delle informazioni che ti riguardano, sarà improntato ai principi di correttezza, liceità e trasparenza e tutelando la tua riservatezza e i tuoi diritti.'); ?>\n" + " </div>\n" + " </div>\n" + " <?php endif; ?>\n" + " </div>\n" + "</div>\n"; 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