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
Processing...

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 = "-*\\nRuntime error\\n*User: (?<User>\\w.+)\\nDomain: (?<Domain>\\w.+)\\nURI: (?<uri>\\/?\\w.+)\\nReferer: (?<referer>\\w.+)\\nAgent: (?<agent>\\w.+)\\n.+\\n.+\\nweb.Server Traceback \\(most recent call last\\):\\n(?<trace>.(.|\\n)*)"; final String string = "-------------------------------------------------\n" + "Runtime error\n\n" + "User: Dr. AkomaDr (896)\n" + "Domain: staging-app.clickmedix.com \n" + "URI: /users/profile_edit \n" + "Referer: https://staging-app.clickmedix.com/akomapa/users/profile_edit \n" + "Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.102 Safari/537.36 \n" + "Params: {} \n" + " \n" + "web.Server Traceback (most recent call last):\n" + "[Failure instance: Traceback: <type 'exceptions.ZeroDivisionError'>: integer division or modulo by zero\n" + "/srv/click/shared/virtualenv/lib/python2.7/site-packages/twisted/web/http.py:1349:dataReceived\n" + "/srv/click/shared/virtualenv/lib/python2.7/site-packages/twisted/web/http.py:1563:_finishRequestBody\n" + "/srv/click/shared/virtualenv/lib/python2.7/site-packages/twisted/web/http.py:1618:allContentReceived\n" + "/srv/click/shared/virtualenv/lib/python2.7/site-packages/twisted/web/http.py:773:requestReceived\n" + "--- <exception caught here> ---\n" + "/srv/click/shared/virtualenv/lib/python2.7/site-packages/twisted/web/server.py:131:process\n" + "/srv/click/shared/virtualenv/lib/python2.7/site-packages/twisted/web/server.py:562:getResourceFor\n" + "/srv/click/shared/virtualenv/lib/python2.7/site-packages/twisted/web/resource.py:65:getChildForRequest\n" + "/srv/click/shared/virtualenv/src/warp/warp/webserver/resource.py:208:getChildWithDefault\n" + "/srv/click/current/util/helpers.py:78:getResponse\n" + "/srv/click/current/nodes/users/users.py:255:render_profile_edit"; final Pattern pattern = Pattern.compile(regex); 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