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 = "Content-ID:\\h+<c4d149e6-3f6a-4aa8-bd07-244c92bdc262-2@cxf.apache.org>\\R\\s*((?:(?!--uuid).*\\R)*)--uuid"; final String string = "HTTP/1.1 200 OK\n" + "Date: ...\n" + "Server: .....\n" + "Set-Cookie: ....; Path=/; HttpOnly\n" + "Set-Cookie: ...; Path=/; HttpOnly\n" + "Content-Type: multipart/related; type=\"application/xop+xml\"; boundary=\"uuid:0f7fa750-c317-4039-897a-a90685b00d29\"; start=\"<...>\"; start-info=\"text/xml\"\n" + "Keep-Alive: timeout=5, max=99\n" + "Connection: Keep-Alive\n" + "Transfer-Encoding: chunked\n\n" + "--uuid:0f7fa750-c317-4039-897a-a90685b00d29\n" + "Content-Type: application/xop+xml; charset=UTF-8; type=\"text/xml\";\n" + "Content-Transfer-Encoding: binary\n" + "Content-ID: <root.message@cxf.apache.org>\n\n" + "<soap:Envelope xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\"><soap:Body><ns2:downloadAttachResponse xmlns:ns2=\"http://..../\"><return><errStr></errStr><result>0</result><contentFile><xop:Include xmlns:xop=\"http://www.w3.org/2004/08/xop/include\" href=\"cid:c4d149e6-3f6a-4aa8-bd07-244c92bdc262-2@cxf.apache.org\"/></contentFile></return></ns2:downloadAttachResponse></soap:Body></soap:Envelope>\n" + "--uuid:0f7fa750-c317-4039-897a-a90685b00d29\n" + "Content-Type: application/octet-stream\n" + "Content-Transfer-Encoding: binary\n" + "Content-ID: <c4d149e6-3f6a-4aa8-bd07-244c92bdc262-2@cxf.apache.org>\n\n" + "%PDF-1.4\n" + "...\n\n" + " LOTS OF BINARY CODE HERE FOR THE PDF\n\n" + "--uuid:0f7fa750-c317-4039-897a-a90685b00d29--\"\n"; 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