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

/
/
g

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 = "\\\"(?<my_field1>xyz-[^\\\"]*)\\\":\\\"(?<my_field2>[^\\\"]*)"; final String string = " 2017-06-27 14:35:38.000 INFO [http-nio-0.0.0.0-19752-exec-4 - RequestResponseLoggerFilter] SessionID 2017-06-28-10:31:01-0855306 correlationID:bbacfa29-095d-49c0-b146-fe456h417ecbb681 \"Request\" : {\"top\":{\"ref\":\"https://abc.com\",\"adrum\":\"isAjax:true\",\"content-length\":\"199\",\"xyz-id\":\"123456\",\"origin\":\"https://offline.xyz.com\",\"xyz-authenticationprovider\":\"kbc\",\"xyz-kbc-entry\":\"ipad\",\"xyz-originaluri\":\"/kpi/abcf\",\"via\":\"http/1.1 xyz.com\",\"xyz-hyt-entrydomain\":\"mb\",\"xyz-ipaddress\":\"117.00.109.103\",\"xyz-originatorauthentication\":\"VUJTLdGhlbnRpY2F0aW9uTW5hbFVyaT0lMkZhcGklMkZ3bWElMkZjcmVkaXQtY2FyZC1wYXltZW50cyUyRnYxJTJGc2NoZWR1bGVkJTJGYWRkJlVCUy1SZXF1ZXN0QmFzZVVybD1odHRwcyU\",\"x-forwarded-host\":\"offline.xyz.com\",\"xyz-isuseraccessinganyaddressinternally\":\"false\",\"x-forwarded-prefix\":\"/api\",\"xyz-isuseraccessinginternally\":\"false\",\"host\":\"offline.xyz.com\",\"content-type\":\"application/json\",\"xyz-hyt-hashregistrationid\":\"61fa7e9eb9afca3c09412a10fb02986d\",\"accept-language\":\"en-us\",\"xyz-authenticationlevel\":\"25\",\"x-forwarded-proto\":\"https\",\"dnt\":\"1\",\"x-forwarded-for\":\"173.66.169.203\",\"xyz-requestbaseurl\":\"https://offline.xyz.com/api\",\"accept\":\"*/*\",\"xyz-hyt-registrationid\":\"123456\",\"x-forwarded-server\":\"148.112.147.17\",\"singularityheader\":\"appId=7*ctrlguid=123456*acctguid=3f5d5ee2-41b3-4e59-ad10-de0b93044*ts=1498660534590*btid=2206*id=9497e8be-3275-417b-9893-30dbcca2d0*exitid=2*unresolvedexitid=164*cidfrom=148*etypeorder=CUSTOM*esubtype=CUSTOM*cidto=545\",\"xyz-hyt-sessionid\":\"2017-06-28-10:31:01-085\",\"xyz-isproxyuser\":\"false\",\"xyz-isemployee\":\"false\",\"xyz-hyt-entrypoint\":\"Mens\",\"accept-encoding\":\"gzip,deflate\",\"user-agent\":\"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/603.2.5 (KHTML, like Gecko) Version/10.1.1 Safari/603.2.5\",\"xyz-iscallersecure\":\"true\"},\"correlationId\":\"bbddfa29-09fd-45c0-b136-fe417ecbb681\"}"; final Pattern pattern = Pattern.compile(regex); 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