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

/
/

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 = "^(?<time>[^ ]* [^ ]* [^ ]*) (?<host>[^ ]*) date=(?<forti_date>[^ ]*) time=(?<forti_time>[^ ]*) devname=(?<dev_name>[^ ]*) device_id=(?<dev_id>[^ ]*) log_id=(?<log_id>[^ ]*) type=(?<type>[^ ]*) subtype=(?<subtype>[^ ]*) pri=(?<pri>[^ ]*) vd=(?<vd>[^ ]*) src=(?<src>[^ ]*) src_port=(?<src_port>[^ ]*) src_int=\"(?<src_int>[^ ]*)\" dst=(?<dst>[^ ]*) dst_port=(?<dst_port>[^ ]*) dst_int=\"(?<dst_int>[^ ]*)\" SN=(?<SN>[^ ]*) status=(?<status>[^ ]*) policyid=(?<policy_id>[^ ]*) dst_country=\"(?<dst_country>[^ ]*)\" src_country=\"(?<src_country>[^ ]*)\" service=(?<service>[^ ]*) proto=(?<proto>[^ ]*) duration=(?<duration>[^ ]*) sent=(?<sent>[^ ]*) rcvd=(?<rcvd>[^ ]*)$"; final String string = "Jan 10 06:00:00 172.24.0.14 date=2016-01-10 time=05:59:59 devname=CNTFI1-FG3040B-02-01 device_id=FG3K0D3I11700008 log_id=0038000004 type=traffic subtype=other pri=notice vd=VDOM1 src=10.172.24.133 src_port=24687 src_int=\"VLAN889\" dst=10.172.18.144 dst_port=1433 dst_int=\"VLAN807\" SN=3504861876 status=start policyid=4816 dst_country=\"Reserved\" src_country=\"Reserved\" service=MS-SQL proto=6 duration=0 sent=0 rcvd=0"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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