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 = "date_modified(?<date_modified>(?:.*?\\n?)*?)internal_id(?<internal_id>(?:.*?\\n?)*?)task(?<task>(?:.*?\\n?)*?)priority(?<priority>(?:.*?\\n?)*?)status(?<status>(?:.*?\\n?)*?)task_status(?<task_status>(?:.*?\\n?)*?)created(?<created>(?:.*?\\n?)*?)assigned(?<assigned>(?:.*?\\n?)*?)date_created(?<date_created>(?:.*?\\n?)*?)date_started(?<date_started>(?:.*?\\n?)*?)date_due(?<date_due>(?:.*?\\n?)*?)date_completed(?<date_completed>(?:.*?\\n?)*?)bunit(?<bunit>(?:.*?\\n?)*?)task_vendor(?<task_vendor>(?:.*?\\n?)*?)task_category(?<task_category>(?:.*?\\n?)*?)customer(?<customer>(?:.*?\\n?)*?)cust_name(?<cust_name>(?:.*?\\n?)*?)cust_territory(?<cust_territory>(?:.*?\\n?)*?)contact(?<contact>(?:.*?\\n?)*?)time_date(?<time_date>(?:.*?\\n?)*?)time_duration(?<time_duration>(?:.*?\\n?)*?)comment(?<comment>(?:.*?\\n?)*?)opportunity(?<opportunity>(?:.*?\\n?)*?)opp_status(?<opp_status>(?:.*?\\n?)*?)opp_engineer(?<opp_engineer>(?:.*?\\n?)*?)transaction(?<transaction>(?:.*?\\n?)*?)yeg_id(?<yeg_id>(?:.*?\\n?)*?)Recent Changes"; final String string = "date_modified21-DECEMBER-2020 12:25 PMinternal_id313017task2nd Year Annual\n" + "billing pricing -34515priorityMediumstatusCompletedtask_statusAllocatedcreated\n" + "Bernadine PereraassignedBernadine Pereradate_created21-DECEMBER-2020 12:25 PM\n" + "date_started21-DECEMBER-2020date_due21-DECEMBER-2020date_completed\n" + "21-DECEMBER-2020bunitOperationstask_vendorSplunktask_categoryOthercustomer\n" + "cust_namecust_territorycontacttime_datetime_durationcommentopportunityopp_status\n" + "opp_engineertransaction yeg_idRecent Changes\n\n" + "DateSet byContextTypeFieldOld ValueNew Value21-DECEMBER-2020 12:25 PMBernadine\n" + "PereraUISetStart Date21-DECEMBER-2020 12:00 Utc21-DECEMBER-2020 12:25 PM\n" + "Bernadine PereraUISetOwnerBernadine Perera21-DECEMBER-2020 12:25 PMBernadine\n" + "PereraUISetAssignedBernadine Perera21-DECEMBER-2020 12:25 PMBernadine PereraUI\n" + "SetBusiness UnitOperations21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask\n" + "CategoryOther21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask StateAllocated\n" + "21-DECEMBER-2020 12:25 PMBernadine PereraUISetTask VendorSplunk21-DECEMBER-2020\n" + "12:25 PMBernadine PereraUICreateRecordTASK313017You requested to receive an\n" + "email alert for this record. Click here to modify your email alerts\n" + "[https://55349.app.netsuite.com/app/center/userprefs.nl?sc=-29&selectedtab=alerts]"; 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