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

r"
"

Test String

Substitution

Processing...

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 = "(?P<date>\\S{3}\\s\\d{1,3}\\s\\d{2}\\:\\d{2}\\:\\d{2})\\s(?P<device>\\S+)\\s\\S\\=(?P<src>\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3})\\:\\s\\S\\=\\\"(?P<user>.*?)\\\"\\s\\S\\=\\d+\\s\\S\\=\\S\\s\\S\\=\\d+\\s\\S\\=\\d+\\s\\S+\\=\\d\\s\\S{1,3}\\=.*?type=\\\".*?\\\"\\s.*?meth=(?P<type>\\S+)\\s\\S+\\=\\\"(?P<url>.*?)\\\"\\s\\S{2}\\=\\\"(?P<agent>.*?)\\\"\\s\\S{1,3}\\=\\\"(?P<url2>.*?)dom\\=\\\"(?P<domain>.*?)\\\".*?target_ip\\=\\\"(?P<dest>\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3})\\\".*"; final String string = "Oct 18 06:27:03 WS2000.wnins.com h=172.16.20.74: u=\"WNINS\\\\rehetzel\" s=200 X=+ t=1445149621 T=44767 Ts=0 act=1 cat=\"0x2200000008\" app=\"-\" rsn=- threat=\"-\" type=\"image/jpeg\" ctype=\"image/jpeg\" sav-ev=- sav-dv=- uri-dv=- cache=- in=471 out=990 meth=GET ref=\"http://www.techrepublic.com/blog/the-enterprise-cloud/how-do-i-assign-permissions-to-users-to-see-sql-agent-jobs/\" ua=\"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.99 Safari/537.36\" req=\"GET http://d.pzkysq.pink/5ET3nslK.jpg?z=715211411411 HTTP/1.1\" dom=\"pzkysq.pink\" filetype=\"-\" rule=\"0\" filesize=518 axtime=0.000455 fttime=0.000043 scantime=- src_cat=\"0x2000000008\" labs_cat=\"0x2000000008\" dcat_prox=\"-\" target_ip=\"204.93.43.48\" labs_rule_id=\"0\" reqtime=0.000 adtime=0.000000 ftbypass=- os=Windows authn=17 auth_by=ntlm dnstime=0.000009 quotatime=-"; final String subst = ""; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceFirst(subst); System.out.println("Substitution result: " + result); } }

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