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 = "([a-z_\\s]+):(.*)"; final String string = "audit_schema_version:1\n" + "event_time:2020-01-23 02:04:52.8531183\n" + "sequence_number:1\n" + "action_id:LGIF\n" + "succeeded:false\n" + "is_column_permission:false\n" + "session_id:0\n" + "server_principal_id:0\n" + "database_principal_id:0\n" + "target_server_principal_id:0\n" + "target_database_principal_id:0\n" + "object_id:0\n" + "user_defined_event_id:0\n" + "transaction_id:0\n" + "class_type:LX\n" + "duration_milliseconds:0\n" + "response_rows:0\n" + "affected_rows:0\n" + "client_ip:10.122.11.71\n" + "permission_bitmask:00000000000000000000000000000000\n" + "sequence_group_id:259EA444-6A54-41A4-AB05-543F2CA2759D\n" + "session_server_principal_name:\n" + "server_principal_name:iamfake\n" + "server_principal_sid:\n" + "database_principal_name:\n" + "target_server_principal_name:\n" + "target_server_principal_sid:\n" + "target_database_principal_name:\n" + "server_instance_name:2019DB1\n" + "database_name:\n" + "schema_name:\n" + "object_name:\n" + "statement:Login failed for user 'iamfake'. Reason: Could not find a login matching the name provided. [CLIENT: 10.1.11.71]\n" + "additional_information:<action_info xmlns=\"http://schemas.microsoft.com/sqlserver/2008/sqlaudit_data\"><pooled_connection>0</pooled_connection><error>0x00004818</error><state>5</state><address>10.1.11.71</address></action_info>\n" + "user_defined_information:\n" + "application_name:Microsoft® Windows® Operating System\n" + "."; 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