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 = "nifi-api\\/(?<your_field>[^\\/]+)"; final String string = "2021-04-13 23:54:59,614 INFO [NiFi Web Server-54351] o.a.n.w.s. Attempting request for (<kdave7><l.com><CN=.com, OU=Middleware Utilities,L=Phoenix, ST=Arizona, C=US>) PUT https://lpdosputb50088.phx.bvc.com:9091/nifi-api/process-groups/9c673790-e123-1a1b-9c0d-d1adf4af91cb/variable-registry \n\n" + "2021-04-13 23:54:59,617 INFO [NiFi Web Server-201257] o.a.n.w.s.NiFiAuthenticationFilter Attempting request for (<kdave7>><CN=lpdosputb50090.phx.aexp.com, OU=Middleware Utilities, L=Phoenix, ST=Arizona, C=US>) PUT https://lpdosputb50089.phx.abc.com:9091/nifi-api/process-groups/9c673790-e123-1a1b-9c0d-d1adf4af91cb/variable-registry\n\n" + "2021-04-13 23:54:41,185 INFO [NiFi Web Server-54256] o.a.n.w.s.NiFiAuthenticationFilter Attempting request for (<JWT token>) GET https://ecpnifiblaze-dev.poi.com/nifi-api/processors/cbd8ff04-0178-1000-0000-000035805b48 "; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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