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 = "(where|and|or)\\s*([^\\s=]*?)\\s*(=|<>|>=|=<|>|<)\\s*(\"|'|\\\\\"|\\\\')([^\\4]*?)\\4"; final String string = "REPLACE active_watchers_log SET sent_msg=\"NOTIFY sip:995582134@192.168.26.5:5062 SIP/2.0\n" + "Via: SIP/2.0/UDP 10.23.0.2;branch=z9hG4bKfd9d.445c5656000000000000000000000000.0\n" + "To: <sip:995582134@teste.sip.90e9.com>;tag=89b8ace0d56977e7\n" + "From: <sip:user_7z7b6s@teste.sip.90e9.com>;tag=9e489e1f14886363a3aeebf53b8dbf2c-4976\n" + "CSeq: 34 NOTIFY\n" + "Call-ID: bec506c8-48da1ac1@192.168.26.5\n" + "Content-Length: 277\n" + "Max-Forwards: 70\n" + "Event: dialog\n" + "Contact: <sip:10.23.0.2:5060;transport=udp>\n" + "Subscription-State: active;expires=600\n" + "Content-Type: application/dialog-info+xml\n\n" + "<?xml version=\\\"1.0\\\"?>\n" + "<dialog-info xmlns=\\\"urn:ietf:params:xml:ns:dialog-info\\\" version=\\\"34\\\" state=\\\"full\\\" entity=\\\"sip:user_7z7b6s@teste.sip.90e9.com\\\">\n" + " <dialog id=\\\"615293b33c62dec073e05d9421e9f48b\\\" direction=\\\"recipient\\\">\n" + " <state>terminated</state>\n" + " </dialog>\n" + "</dialog-info>\n" + "\", received_msg=\"SIP/2.0 200 OK\n" + "To: <sip:995582134@teste.sip.90e9.com>;tag=89b8ace0d56977e7\n" + "From: <sip:user_7z7b6s@teste.sip.90e9.com>;tag=9e489e1f14886363a3aeebf53b8dbf2c-4976\n" + "Call-ID: bec506c8-48da1ac1@192.168.26.5\n" + "CSeq: 34 NOTIFY\n" + "Via: SIP/2.0/UDP 10.23.0.2;branch=z9hG4bKfd9d.445c5656000000000000000000000000.0\n" + "Server: Cisco/SPA504G-7.6.0\n" + "Content-Length: 0\n\n" + "\", time=1453481591, result=200 where pres_uri=\"sip:user_7z7b6s@teste.sip.90e9.com\" and callid=\"bec506c8-48da1ac1@192.168.26.5\" and watcher_user=\\\"995582134\\\" and watcher_domain=\\'teste.sip.90e9.com\\' and to_user=\"user_7z7b6s\" and to_domain=\"teste.sip.90e9.com\""; 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