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 = "^.*(?P<message>\\{.*\\})"; final String string = "{\"channel\":\"crm_process_booking_log\",\"log_type\":\"DEBUG\",\"index_name\":\"crm_process_booking_log\",\"index_type\":\"crm_process_booking_log\",\"error_type\":0,\"message\":{\"data\":{\"STEP\":\"Adding Post Data\",\"post_data\":{\"customer\":[{\"relation\":\"others\",\"age\":28,\"dob\":null,\"gender\":\"F\",\"email\":null,\"customer_id\":\"66aff7d8-cd9b-4796-bf17-e66088c3565a\",\"customer_name\":\"Prena\",\"contact_number\":null}],\"slot\":{\"slot_id\":\"684178718\"},\"gender\":\"M\",\"mobile\":\"6700670875\",\"email\":\"siddhant.khanna_testi_blr+rahul@acko.tech\",\"state\":\"26\",\"cityId\":\"23\",\"latitude\":28.5101825,\"longitude\":77.0682661,\"address\":\"sector 21, gurgaon, Gurgaon, Haryana, 122016\",\"zipcode\":\"122016\",\"landmark\":\"home\",\"altmobile\":false,\"altemail\":false,\"package\":[{\"deal_id\":[\"package_216\"]}],\"customer_calling_number\":\"6700670875\",\"billing_cust_name\":\"Rahu\",\"sub_locality\":\"sector 21, gurgaon, Gurgaon, Haryana, 122016\",\"hard_copy\":0,\"vendor_booking_id\":false,\"vendor_billing_user_id\":\"4rWzYn5NOhEgNPdiVGWiRA\",\"payment_option\":\"invoice\",\"discounted_price\":0,\"sample_collected\":\"n\",\"role_id\":0,\"search_by\":\"customer_mobile\",\"channel_partner\":\"3\",\"channel_partner_user\":\"5490\",\"booked_source\":\"api\",\"zip_search\":2,\"calling_from\":\"external_api\",\"b2bNewExistingUser\":false,\"user_id_ajax\":\"\",\"whatsappconcent\":1,\"billing_zone_id\":\"53\",\"zone_id\":\"53\",\"amzn_trace_id\":\"Root=1-65c33f1c-29fe535658001b076140677c\",\"billing_cust_city\":\"gurgaon\",\"billing_cust_city_id\":\"23\",\"locality\":\"541\",\"channel_type\":\"3\",\"channel_user\":\"5490\"},\"amzn_trace_id\":\"Root=1-65c33f1c-29fe535658001b076140677c\"},\"calling_trace\":{\"file\":\"\\/var\\/www\\/newcrm-t25\\/application\\/controllers\\/crmuser\\/crmorder.php\",\"line\":1227,\"function\":\"addProcessBookingLog\",\"class\":\"Enterprise_logger\"}},\"amzn_trace_id\":\"Root=1-65c33f1c-29fe535658001b076140677c\",\"nginx_request_id\":\"c93176430784c9dd4e32e35541e6e31a\",\"timestamp\":\"2024-02-07 13:58:12\"}"; 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