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
Processing...

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 = "^(?:[^ ]*, )*?(?<client_ip>[^ ]*) (?<host>[^ ]*) (?<user>[^ ]*) \\[(?<time>[^\\]]*)\\] \"(?<method>\\S+)(?: +(?<uri>[^\\\"]*?)(?: +\\S*)?)?\" \"(?<body>.*?)\" (?<code>[^ ]*) (?<size>[^ ]*)(?: \"(?<referer>[^\\\"]*)\" \"(?<agent>[^\\\"]*)\")? (?<request_time>[^ ]*) (?<upstream_response_time>.*)$"; final String string = "140.207.54.75, 100.97.90.103, 10.117.43.51 - - [24/Jun/2016:05:32:02 +0800] \"POST /weixin/notify/open/authorize?signature=2ac1ca77cf259bc2b234e3261e320db698c53a9c&timestamp=1466717523&nonce=1035843400&encrypt_type=aes&msg_signature=2712811c2c6cf0cacdfb65461ab4c23ec36a3c61 HTTP/1.0\" \"<xml>\\x0A <AppId><![CDATA[wxe484f12197737223]]></AppId>\\x0A <Encrypt><![CDATA[By8VnMuxv0R05S8Zl4+eY5Nq5nzqjNcTN8ljzfIOBM/GSzYMEPXwNck62DjFqnSbOkHK0xZ4uLJkc09Bnomr4Q/Zdt98YGNcdXmW4lDA8rQPfJU97hRfM5EwWGUI1n2EOgk8rSBVNwYE08DMdtXy6NVtPEi3JVktUlq0X5DkMhQg+YchJTAeiw+zbXoqYjWWX+prSDPXFArLu+6jzKliB8i+B9R2uaqtx+f2ceRY2vPoVP4p9xg2+ViOCM7n3rA8hjvk9Qf2pdeAvLsJxon/NTRkSAiUDKYwEwT5zF5sJ7S0nem3PyXHtiNczIDeNIIhl0lbsfY4muVuDx0I0GFp7PH/mJM9OdpJSarE6znxTAuij151NsmiehZsCAEQqKhbiVCCyvvdHAmWvZn1UZ86XSF5d0r1HBPeUYegsHfuj7lOpkalB65Br3DVDEkPjiCljwlcx7R5rAutvRHzBx2Y/A==]]></Encrypt>\\x0A</xml>\\x0A\" 200 7 \"-\" \"Mozilla/4.0\" 0.008 0.007"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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