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

/
/
gxm

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 = "^=((?<component>[^ ]*(SUPERVISOR))|(?<severity>[^ ]*(INFO))).*\\s+(?<time>[^ =]*)\\s+[=]*\\n(?<message>(?s)^(.*?)(?:(?:\\r*\\n){2}))"; final String string = "=SUPERVISOR REPORT==== 5-Jul-2017::14:10:58 ===\n" + " Supervisor: {<0.15737.0>,amqp_channel_sup_sup}\n" + " Context: shutdown_errorhttps://regex101.com/r/QpRINz/1/tests\n" + " Reason: shutdown\n" + " Offender: [{nb_children,1},\n" + " {name,channel_sup},\n" + " {mfargs,\n" + " {amqp_channel_sup,start_link,\n" + " [direct,<0.15736.0>,\n" + " <<\"<rabbit@rabbitmq-default-Control.3.15736.0>\">>]}},\n" + " {restart_type,temporary},\n" + " {shutdown,brutal_kill},\n" + " {child_type,supervisor}]\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:03 ===\n" + "Starting RabbitMQ 3.4.4 on Erlang 17.5.6\n" + "Copyright (C) 2007-2014 GoPivotal, Inc.\n" + "Licensed under the MPL. See http://www.rabbitmq.com/\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:03 ===\n" + "node : rabbit@rabbitmq-default-Control\n" + "home dir : /var/lib/rabbitmq\n" + "config file(s) : /etc/rabbitmq/rabbitmq.config\n" + "cookie hash : jlzhQcHOuBZ03iv7GFo/pQ==\n" + "log : /var/log/rabbitmq/rabbit@rabbitmq-default-Control.log\n" + "sasl log : /var/log/rabbitmq/rabbit@rabbitmq-default-Control-sasl.log\n" + "database dir : /var/lib/rabbitmq/mnesia/rabbit@rabbitmq-default-Control\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "Limiting to approx 65436 file handles (58890 sockets)\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "Memory limit set to 58079MB of 145198MB total.\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "Disk free limit set to 50MB\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "msg_store_transient: using rabbit_msg_store_ets_index to provide index\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "msg_store_persistent: using rabbit_msg_store_ets_index to provide index\n\n" + "=WARNING REPORT==== 24-Jul-2017::08:44:05 ===\n" + "msg_store_persistent: rebuilding indices from scratch\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "started TCP Listener on 10.60.2.90:5672\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "accepting AMQP connection <0.4941.0> (10.60.2.82:47767 -> 10.60.2.90:5672)\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "accepting AMQP connection <0.4949.0> (10.60.2.82:47768 -> 10.60.2.90:5672)\n\n" + "=INFO REPORT==== 24-Jul-2017::08:44:05 ===\n" + "accepting AMQP connection <0.4952.0> (10.60.2.82:47769 -> 10.60.2.90:5672)\n\n" + "=SUPERVISOR REPORT==== 5-Jul-2017::23:11:58 ===\n" + " Supervisor: {<0.23464.1>,amqp_channel_sup_sup}\n" + " Context: shutdown_error\n" + " Reason: shutdown\n" + " Offender: [{nb_children,1},\n" + " {name,channel_sup},\n" + " {mfargs,\n" + " {amqp_channel_sup,start_link,\n" + " [direct,<0.23463.1>,\n" + " <<\"<rabbit@rabbitmq-default-Control.3.23463.1>\">>]}},\n" + " {restart_type,temporary},\n" + " {shutdown,brutal_kill},\n" + " {child_type,supervisor}]\n\n" + "=SUPERVISOR REPORT==== 6-Jul-2017::06:20:58 ===\n" + " Supervisor: {<0.22665.2>,amqp_channel_sup_sup}\n" + " Context: shutdown_error\n" + " Reason: shutdown\n" + " Offender: [{nb_children,1},\n" + " {name,channel_sup},\n" + " {mfargs,\n" + " {amqp_channel_sup,start_link,\n" + " [direct,<0.22664.2>,\n" + " <<\"<rabbit@rabbitmq-default-Control.3.22664.2>\">>]}},\n" + " {restart_type,temporary},\n" + " {shutdown,brutal_kill},\n" + " {child_type,supervisor}]\n"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS | 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