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

Substitution

Processing...

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 = "<\\/?(\\d)"; final String string = "<?xml version=\"1.0\"?>\n" + "<data>\n" + " <client_name>Awesome Client</client_name>\n" + " <account_number/>\n" + " <date_created>02/12/2016</date_created>\n" + " <form_number>4126</form_number>\n" + " <customer_po/>\n" + " <terms_name>Credit Card</terms_name>\n" + " <date_shipped>12/31/1969</date_shipped>\n" + " <billing_contact_email/>\n" + " <billing_contact_address_line_1/>\n" + " <billing_contact_address_line_2/>\n" + " <billing_contact_address_line_3/>\n" + " <billing_contact_address_line_4/>\n" + " <billing_contact_address_city/>\n" + " <billing_contact_address_state>British Columbia</billing_contact_address_state>\n" + " <billing_contact_address_postal/>\n" + " <billing_contact_address_country>Canada</billing_contact_address_country>\n" + " <shipping_contact_address_line_1/>\n" + " <shipping_contact_address_line_2/>\n" + " <shipping_contact_address_line_3/>\n" + " <shipping_contact_address_line_4/>\n" + " <shipping_contact_address_city/>\n" + " <shipping_contact_address_state>British Columbia</shipping_contact_address_state>\n" + " <shipping_contact_address_postal/>\n" + " <shipping_contact_address_country>Canada</shipping_contact_address_country>\n" + " <billing_contact_first_name>another</billing_contact_first_name>\n" + " <billing_contact_last_name>client</billing_contact_last_name>\n" + " <client_rep_full_name>Rob Montebelli</client_rep_full_name>\n" + " <order_rep_full_name>Mark Graham</order_rep_full_name>\n" + " <job_name>77777</job_name>\n" + " <job_number>2620</job_number>\n" + " <event_type>Donor Gift</event_type>\n" + " <due_date>02/12/2016</due_date>\n" + " <shipping_method/>\n" + " <currency>CAD</currency>\n" + " <total_taxes>0.00</total_taxes>\n" + " <total_subtotal>1,760.16</total_subtotal>\n" + " <total>1,760.16</total>\n" + " <items>\n" + " <item0>\n" + " <taxes>\n" + " <0>E</0>\n" + " </taxes>\n" + " <title>1889-24</title>\n" + " <quantity>6</quantity>\n" + " <description>Carhartt (R) Signature Utility Duffel; TBD TBD</description>\n" + " <unit_price>159.32</unit_price>\n" + " </item0>\n" + " <item1>\n" + " <taxes>\n" + " <0>E</0>\n" + " </taxes>\n" + " <title>0022-56</title>\n" + " <quantity>12</quantity>\n" + " <description>Zoom (TM) DayTripper Sling Compu-Messenger; TBD TBD</description>\n" + " <unit_price>67.02</unit_price>\n" + " </item1>\n" + " </items>\n" + "</data>"; final String subst = "<number$1"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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