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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /(\d+-\d+-\d+\s\S+)\s+(\w+)\s(\d+)\s---\s(\S+.\S+)\s(\S+\s+:)\s(\S+.*)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(\\d+-\\d+-\\d+\\s\\S+)\\s+(\\w+)\\s(\\d+)\\s---\\s(\\S+.\\S+)\\s(\\S+\\s+:)\\s(\\S+.*)', 'gm') const str = `2019-12-27 13:52:38.201 INFO 1 --- [Thread-8] j.LocalContainerEntityManagerFactoryBean : Closing JPA EntityManagerFactory for persistence unit 'default' 2019-12-27 13:52:39.535 INFO 1 --- [Thread-8] com.alibaba.druid.pool.DruidDataSource : {dataSource-1} closed 2019-12-27 13:52:39.538 INFO 1 --- [Thread-8] com.netflix.discovery.DiscoveryClient : Shutting down DiscoveryClient ... 2019-12-27 13:52:42.539 INFO 1 --- [Thread-8] com.netflix.discovery.DiscoveryClient : Unregistering ... 2019-12-27 13:52:42.540 WARN 1 --- [DiscoveryClient-0] c.netflix.discovery.TimedSupervisorTask : task supervisor shutting down, can't accept the task 2019-12-27 13:52:42.597 INFO 1 --- [Thread-8] com.netflix.discovery.DiscoveryClient : Completed shut down of DiscoveryClient 2019-12-27 13:52:43.329 WARN 1 --- [XNIO-1 task-15] c.n.eureka.resources.InstanceResource : Not Found (Renew): RPLUS-SERVICE-COMMUNITY - 69bce99f652f:rplus-service-community:20090 `; // 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