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

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^\\s*(?<time>[^ ]* {1,2}[^ ]* [^ ]*) \\[(?<pid>\\d+)\\] (?<macid>[\\-\\w]*)\\s*(?<component>\\w*):\\s+(?<severity>\\w+):\\s+(?<action>\\w+):\\s+(?<action_status>\\w+) (?<mesage>[^\\(]*) (\\((?<meta>.*)\\))$"; final String string = "Sep 19 09:23:01 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-64-6e/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 09:23:06 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xe2bf50 0)\n" + "Sep 19 09:30:53 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-64-50/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 09:30:58 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xe2e450 0)\n" + "Sep 19 09:37:59 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-65-68/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 09:38:04 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xe372d0 0)\n" + "Sep 19 09:43:25 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Forwarding cib_modify operation for section nodes to master (origin=local/crm_attribute/4)\n" + "Sep 19 09:43:25 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-64-6e/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 09:43:30 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xe2be50 0)\n" + "Sep 19 09:46:55 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-64-50/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 09:47:00 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xeead20 0)\n" + "Sep 19 09:54:03 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-65-68/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 09:54:08 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0x129d470 0)\n" + "Sep 19 10:02:51 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-64-50/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 10:02:56 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xe2e450 0)\n" + "Sep 19 10:03:38 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Forwarding cib_modify operation for section nodes to master (origin=local/crm_attribute/4)\n" + "Sep 19 10:03:38 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-64-6e/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 10:03:43 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xb60f30 0)\n" + "Sep 19 10:10:11 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-65-68/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 10:10:16 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0xd963e0 0)\n" + "Sep 19 10:18:44 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_request: Completed cib_modify operation for section nodes: OK (rc=0, origin=d2c-76-8a-ac-64-50/crm_attribute/4, version=0.1352.0)\n" + "Sep 19 10:18:49 [16818] d2c-76-8a-ac-64-6e cib: info: cib_process_ping: Reporting our current digest to d2c-76-8a-ac-64-50: bc17de2aedf4d53c3f4fa8021fffd2b1 for 0.1352.0 (0x129d4f0 0)"; 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