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

const regex = /nifi-api\/(?<your_field>[^\/]+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('nifi-api\\\/(?<your_field>[^\\\/]+)', 'gm') const str = `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 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 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 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions